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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationForeignExchangeLossPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Effective Income Tax Rate Reconciliation, Foreign Exchange Loss, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringCostAndReserveLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring Cost and Reserve [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Other, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentOther_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementGeographicalAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementGeographicalAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Geographical [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Reconciliation of the Change in the Fair Value of Contingent Consideration - Earnout</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other noncurrent liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Liabilities, Noncurrent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Liabilities, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MetenovaHoldingAbMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Metenova Holding AB</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MetenovaHoldingAbMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Metenova Holding AB [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MetenovaHoldingAbMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Metenova Holding AB.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Prepaid Expense and Other Assets, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Prepaid Expense and Other Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Prepaid expenses and other assets</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2025</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level 1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IntangibleAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Intangible Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IntangibleAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IntangibleAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition, Pro Forma Earnings Per Share, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityPublicFloat_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Public Float</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">2027</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssetNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long term deferred tax asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssetNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Deferred Tax Asset Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssetNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination recognized identifiable assets acquired and liabilities assumed deferred tax asset noncurrent.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Schedule of Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule Of Finite Lived And Indefinite Lived Intangible Assets [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Finite Lived And Indefinite Lived Intangible Assets [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Measurements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Disclosures [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax, Policy [Policy Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Useful Life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated Useful Life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CustomerNumberOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Customer number one member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CustomerNumberOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer Number One [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CustomerNumberOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer Number One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentExchangedAmountCancelled_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt istrument cancelled</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentExchangedAmountCancelled_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument exchanged amount cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfIncomeBeforeIncomeTaxTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Income Before Income Tax [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfIncomeBeforeIncomeTaxTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Income Before Income Tax [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfIncomeBeforeIncomeTaxTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Income Before Income Tax [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total unrecognized compensation cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Payments to Acquire Businesses, Net of Cash Acquired, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Businesses, Net of Cash Acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquisitions, net of cash acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Acquisitions, net of cash acquired</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentration Risk Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RDAndCommercializationBasedPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">R D And Commercialization Based Payments</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FiltrationProductsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Filtration Products [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FiltrationProductsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Filtration Products [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermDebtTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-Term Debt, Type [Axis]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MeasurementInputEarnoutDiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Earnout Discount Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfIncomeBeforeIncomeTaxLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Income Before Income Tax [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfIncomeBeforeIncomeTaxLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Income Before Income Tax [Line Items]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="country_SE_lbl" xlink:role="http://www.xbrl.org/2003/role/label">SWEDEN</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SalesRevenuesGoodsNetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total Revenue</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Recognized Identified Assets Acquired and Liabilities Assumed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SubscriptionTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subscription Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SubscriptionTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subscription Transaction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SubscriptionTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Subscription Transaction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_TitleOfIndividualWithRelationshipToEntityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of Individual [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_TitleOfIndividualWithRelationshipToEntityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Relationship to Entity [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_TitleOfIndividualWithRelationshipToEntityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Title of Individual [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessAcquisitionWorkingCapitalAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Working capital adjustment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessAcquisitionWorkingCapitalAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition Working Capital Adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessAcquisitionWorkingCapitalAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business acquisition working capital adjustments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentFaceAmountRemaining_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument face amount remaining</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentFaceAmountRemaining_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Face Amount Remaining</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentFaceAmountRemaining_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Face amount of remaining convertible debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureTextBlockAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Text Block [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAcquiredDuringPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill, Acquired During Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAcquiredDuringPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill arising from Acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncomeTaxesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Income Taxes [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncomeTaxesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Taxes [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncomeTaxesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ForeignEarningsSubjectToOneTimeTransitionTax_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Foreign Earnings Subject To One Time Transition Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ForeignEarningsSubjectToOneTimeTransitionTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Earnings Subject To One Time Transition Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ForeignEarningsSubjectToOneTimeTransitionTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign earnings subject to one time transition tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockOptionAndIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock Option and Incentive Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockOptionAndIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Option And Incentive Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockOptionAndIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2018 Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BioflexAndNtmAcquisitionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">BioFlex And NTM Acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BioflexAndNtmAcquisitionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">BioFlex And NTM Acquisition [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BioflexAndNtmAcquisitionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">NTM Acquisition [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from External Customers by Products and Services [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Product Revenues by Product Line</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liability, long-term</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Repurchase of common stock (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchased During Period, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reconciliation of Assets from Segment to Consolidated [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reconciliation of Assets from Segment to Consolidated [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reconciliation of Assets from Segment to Consolidated [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total Assets by Geographic Area</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_EuropeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Europe [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_EuropeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Europe</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Intangible Assets [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Intangible Assets [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Intangible Assets [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonrecurringAdjustmentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nonrecurring Adjustment [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance at December 31, 2023</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance at December 31, 2022</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities, fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Balance as of December 31, 2021</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Fair Value Disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Liabilities, Fair Value Disclosure, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate debt discount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscount_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Instrument, Unamortized Discount, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Unamortized Discount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscount_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Unamortized debt discount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeSeveranceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Severance &amp; employee-related costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeSeveranceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Severance [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfGoodwillTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Goodwill [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfGoodwillTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Goodwill [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_LeaseIncentives_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lease incentives.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_LeaseIncentives_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease Incentives</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_LeaseIncentives_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less lease incentives</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_LeaseIncentives_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less lease incentives</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VestingDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Vesting [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingAssetReconcilingItemLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Reporting, Asset Reconciling Item [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CapacityOfBioreactors_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">It's represents about capacity of bioreactors.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ReconciliationOfBasicAndDilutedAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reconciliation of Basic and Diluted [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax assets</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetAndLiabilityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Contract Asset, Contract Liability, and Receivable [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ArtesynBiosolutionsHoldingsIrelandLimitedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Metenova Holding AB</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average grant date fair value of share-based awards granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionEffectiveDateOfAcquisition1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business combination date of acquistion</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Comprehensive income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Comprehensive income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill and Intangible Assets, Policy [Policy Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Net of Valuation Allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net deferred tax assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPeriodAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Redemption, Period [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPeriodAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument, Redemption, Period [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Common Stock, Shares, Issued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares issued</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PercentOfExciseTaxOnNetStockRepurchases_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percent of excise tax on net stock repurchases.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PercentOfExciseTaxOnNetStockRepurchases_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percent Of Excise Tax On Net Stock Repurchases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PercentOfExciseTaxOnNetStockRepurchases_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percent of excise tax on net stock repurchases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputReconciliationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total grant date fair value of restricted stock units vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition, Pro Forma Earnings Per Share, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerReceivableAfterAllowanceForCreditLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerReceivableAfterAllowanceForCreditLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Receivable, after Allowance for Credit Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerReceivableAfterAllowanceForCreditLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Contract with Customer, Receivable, after Allowance for Credit Loss, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense and Other Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_WeightedAverageNumberOfSharesDilutiveEffectOfUnvestedPerformanceStockUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Dilutive Effect of Unvested Performance Stock Units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_WeightedAverageNumberOfSharesDilutiveEffectOfUnvestedPerformanceStockUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted average number of shares dilutive effect of unvested performance stock units.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_WeightedAverageNumberOfSharesDilutiveEffectOfUnvestedPerformanceStockUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Dilutive effect of unvested performance stock units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CompensationAndEmployeeBenefitPlansTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Compensation and Employee Benefit Plans [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CompensationAndEmployeeBenefitPlansTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoZeroOneNineNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2019 Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoZeroOneNineNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Zero One Nine Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoZeroOneNineNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two zero one nine notes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireSoftware_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Software</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireSoftware_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Additions to capitalized software costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Long-Term Debt Instruments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Long-term Debt Instruments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesHeldToMaturityGrossUnrealizedGain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Marketable securities, Gross Unrealized Gains</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesHeldToMaturityGrossUnrealizedGain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities Held to Maturity Gross Unrealized Gain</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesHeldToMaturityGrossUnrealizedGain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt securities held to maturity gross unrealized gain.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">2026</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Capital Shares Reserved for Future Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock shares reserved for Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdvertisingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Advertising Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AOCI Attributable to Parent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Other Comprehensive Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquisitions</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AmortizationOfDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Amortization of debt issuance costs</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AmortizationOfDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization Of Debt Issuance Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AmortizationOfDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of debt issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss) [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Other Comprehensive Income (Loss) [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LoansAndLeasesReceivableLeaseFinancingPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease Accounting</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Land_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Land</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesMaturityWithinOneYearAmortizedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt securities maturity within one year amortized cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesMaturityWithinOneYearAmortizedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities Maturity Within One Year Amortized Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesMaturityWithinOneYearAmortizedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt securities maturity within one year amortized cost.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationAwardTrancheTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Tranche Two [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationAwardTrancheTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vest Over Five Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Forfeited/expired/cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid-in Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional Paid-in Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Difference between U.S. and foreign tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Tax Provision (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionsProFormaRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition, Pro Forma Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionsProFormaRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLifeDescriptionOfTermExtensibleEnumeration_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant, and Equipment, Useful Life, Term, Description [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLifeDescriptionOfTermExtensibleEnumeration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant, and Equipment, Useful Life, Term, Description [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeFixedInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Discount Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeFixedInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative, Fixed Interest Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redemption of marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-Sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Business combination contingent consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Consideration Transferred, Liabilities Incurred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent consideration - earnout</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Decrease in fair value of contingent consideration earnouts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CTechnologiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">C Technologies Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CTechnologiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">C Technologies [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CTechnologiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">C Technologies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CTechnologiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">C Technologies, Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringReserveSettledWithoutCash2_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Non-Cash Restructuring Items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringReserveSettledWithoutCash2_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring Reserve, Settled without Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current assets:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, Allowance for Credit Loss, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable, reserve for doubtful accounts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_CounterpartyNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Stockholders' Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationSeparatelyRecognizedTransactionsSettlementOfPreexistingInvoices_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination settlement of preexisting invoices.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationSeparatelyRecognizedTransactionsSettlementOfPreexistingInvoices_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Separately Recognized Transactions Settlement Of Preexisting Invoices</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationSeparatelyRecognizedTransactionsSettlementOfPreexistingInvoices_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business Combination settlement of preexisting invoices</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationSeparatelyRecognizedTransactionsSettlementOfPreexistingInvoices_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Settlement of preexisting liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Securities, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdvertisingCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Advertising Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdvertisingCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Advertising Cost [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Contract with Customer, Including Assessed Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetsByMajorClassTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Acquired Finite-Lived Intangible Assets by Major Class [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetsByMajorClassTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Identified Intangible Assets and Estimated Useful Lives</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Contingent Consideration Earnout Expect to be Required to Settle Include Significant Unobservable Inputs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement Inputs and Valuation Techniques [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Maturity Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Notes, due date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Notes, carrying value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total convertible senior notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total convertible senior notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeContractTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative Contract [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Property, Plant and Equipment, Net, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Property, Plant and Equipment, Net, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, plant and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total property, plant and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillPurchaseAccountingAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Measurement period adjustments</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfStockDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Stock [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AssetsNonCurrentExcludingDifferedTaxAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">The amount of total non-current assets excluding deferred tax assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AssetsNonCurrentExcludingDifferedTaxAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets Non current Excluding Differed Tax Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AssetsNonCurrentExcludingDifferedTaxAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long Lived Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringCharges_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restructuring charges</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringCharges_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Restructuring Charges, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NonMetallicSolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non Metallic Solutions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NonMetallicSolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Non-metallic solutions [Member].</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NonMetallicSolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non Metallic Solutions [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NonMetallicSolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">NMS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProvisionForDoubtfulAccounts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, Credit Loss Expense (Reversal)</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from External Customer [Line Items]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AccumulatedDeficitMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Deficit [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AccumulatedDeficitMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accumulated deficit.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vested and expectd to vest at December 31, 2021</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxLiablitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Tax Liablities Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxLiablitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred tax liablities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIntangibleAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Intangible Assets [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIntangibleAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other intangibles</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RisksAndUncertaintiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Risks and Uncertainties [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unvested at December 31, 2020</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfAmortizedCostAndFairValueDebtSecuritiesHeldToMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tabular disclosure of the fair value held to maturity securities by contractual maturity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfAmortizedCostAndFairValueDebtSecuritiesHeldToMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Amortized Cost and Fair Value Debt Securities Held to Maturity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfAmortizedCostAndFairValueDebtSecuritiesHeldToMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Amortized Cost and Fair Value Held to Maturity Securities by Contractual Maturity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableAllowanceForCreditLossTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, Allowance for Credit Loss [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableAllowanceForCreditLossTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary Of Allowance For Credit Losses For Accounts Receivables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets, fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Fair Value Disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Assets, Fair Value Disclosure, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Operating Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Other Operating Assets, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentConvertibleIntoEquitySettled_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument convertible in to equity settled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentConvertibleIntoEquitySettled_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Convertible Into Equity Settled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentConvertibleIntoEquitySettled_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument convertible in to equity settled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Consideration Transferred, Equity Interests Issued and Issuable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Value of common stock issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FacilityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Facility Domain</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FacilityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Facility [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Preferred Stock, Shares Outstanding, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Preferred Stock, Shares Outstanding, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquisition date fair value of contingent consideration earnout</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfGoodwillTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Goodwill [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfGoodwillTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Changes in Carrying Value of Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveSharesEffectOnBasicEarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">DilutivesharesAbstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveSharesEffectOnBasicEarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive shares, Effect on Basic Earnings Per Share [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveSharesEffectOnBasicEarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of dilutive shares:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Tax Identification Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income before income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Income before income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryFinishedGoodsNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Finished Goods, Net of Reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryFinishedGoodsNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finished products</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Operating Capital [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in operating assets and liabilities, excluding impact of acquisitions:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfDebtIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payment of debt issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfDebtIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of debt issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfDebtIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments of Debt Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OtherDirectorsOrOfficersMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other directors or officers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OtherDirectorsOrOfficersMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Directors Or Officers [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OtherDirectorsOrOfficersMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other directors or officers.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalizedComputerSoftwareGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capitalized Computer Software, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalizedComputerSoftwareGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Computer hardware and software</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-Based Compensation Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Additional Disclosures [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-Average Remaining Contractual Term (in years)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Leases [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FlexbiosysIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">FlexBiosys, Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FlexbiosysIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">FlexBiosys, Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FlexbiosysIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">FlexBiosys, Inc. [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FlexbiosysIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">FlexBiosys, Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Discount rate.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Discount Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Discount rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeInstrumentRiskAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_SegmentGeographicalDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_SegmentGeographicalDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Geographical [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="country_US_lbl" xlink:role="http://www.xbrl.org/2003/role/label">UNITED STATES</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="country_US_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">United States</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Investment Income, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment Income, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Right-of-Use Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease right of use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FacilityExitAndOtherExitCostsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Facility exit and other exit costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FacilityExitAndOtherExitCostsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Facility Exit and Other Exit Costs [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FacilityExitAndOtherExitCostsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Facility exit and other exit costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredFinanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Issuance Costs, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredFinanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Issuance Costs, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredFinanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Unamortized debt issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ExecutiveOfficerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Executive Officer [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ExecutiveOfficerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Awards Granted to Executive Level Employees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesHeldToMaturityEstimatedFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Marketable securities, Estimated Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesHeldToMaturityEstimatedFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities Held to Maturity Estimated Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesHeldToMaturityEstimatedFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt securities held to maturity estimated fair value.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UnlimitedCarryforwardPeriodMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unlimited Carryforward Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UnlimitedCarryforwardPeriodMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unlimited Carryforward Period [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UnlimitedCarryforwardPeriodMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unlimited carryforward period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Retained Earnings (Accumulated Deficit), Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Retained Earnings (Accumulated Deficit), Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Retained Earnings (Accumulated Deficit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings (Accumulated Deficit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated earnings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cumulative effect of accounting changes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncreasedecreaseInOperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">The increase (decrease) during the reporting period in operating lease right of use asset.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncreasedecreaseInOperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease in Operating Lease Right Of Use Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncreasedecreaseInOperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Operating lease right of use assets</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Supplemental disclosure of cash flow information:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IndefiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Indefinite Lived Intangible Assets Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IndefiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Indefinite Lived Intangible Assets Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IndefiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accumulated Earnings/(Deficit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementClassOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Stock [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryRawMaterialsNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Raw Materials, Net of Reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryRawMaterialsNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Raw materials</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Shares, Unvested at December 31, 2023</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Shares, Unvested at December 31, 2022</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted stock units, outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationRepatriationOfForeignEarnings_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationRepatriationOfForeignEarnings_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">U.S. taxation of foreign earnings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Federal Income Tax Expense (Benefit), Continuing Operations, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Federal Income Tax Expense (Benefit), Continuing Operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Federal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected tax at statutory rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncreaseDecreaseInOperatingLeaseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase decrease in operating lease asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncreaseDecreaseInOperatingLeaseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease In Operating Lease Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncreaseDecreaseInOperatingLeaseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase decrease in operating lease asset.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CashCashEquivalentsAndMarketableSecuritiesHeldToMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tabular disclosure of the components of cash, cash equivalents, and marketable securities held to maturity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CashCashEquivalentsAndMarketableSecuritiesHeldToMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalents and Marketable Securities Held to Maturity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CashCashEquivalentsAndMarketableSecuritiesHeldToMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Cash, Cash Equivalents and Marketable Securities Held to Maturity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ConvertibleNotesTransactionCostsOfLiabilityComponent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible notes transaction costs of liability component.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ConvertibleNotesTransactionCostsOfLiabilityComponent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Notes Transaction Costs Of Liability Component</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ConvertibleNotesTransactionCostsOfLiabilityComponent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Transaction costs attributable to liability component</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UnderwriterMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Underwriter.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UnderwriterMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Underwriter [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UnderwriterMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Underwriters</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Stock Options Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from exercise of stock options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Significant Accounting Policies [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Significant Accounting Policies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Prepaid Expenses and Other Current Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Minimum operating lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Minimum operating lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseholdImprovementsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leasehold Improvements, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseholdImprovementsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leasehold improvements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationAwardTrancheOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Tranche One [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationAwardTrancheOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vest Over Three Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IndefiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IndefiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Indefinite Lived Intangible Assets Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IndefiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Indefinite Lived Intangible Assets Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IndefiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected volatility (range), minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PfizerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Pfizer Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PfizerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pfizer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PfizerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Pfizer member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PfizerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Pfizer [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedIncomeTaxesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income taxes payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedIncomeTaxesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Income Taxes, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation of Revenue [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Component [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Component [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DefinedBenefitPlanContributionsByEmployer_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Benefit Plan, Plan Assets, Contributions by Employer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DefinedBenefitPlanContributionsByEmployer_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Defined contribution plan, company contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_APACMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">A P A C Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_APACMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">APAC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_APACMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">APAC</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfSupplementalDisclosureOfCashFlowsRelatedToOperatingLeasesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tabular disclosure of supplemental disclosure for the consolidated statements of cash flows related to operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfSupplementalDisclosureOfCashFlowsRelatedToOperatingLeasesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Supplemental Disclosure Of Cash Flows Related To Operating Leases [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfSupplementalDisclosureOfCashFlowsRelatedToOperatingLeasesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Schedule of Supplemental Disclosure of Cash Flows Related to Operating Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustments to reconcile net income to net cash provided by operating activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ProbabilityOfSuccess_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Probability of Success</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ProbabilityOfSuccess_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Probability of success.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ProbabilityOfSuccess_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Probability of Success</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Frequency [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillForeignCurrencyTranslationGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill, Foreign Currency Translation Gain (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillForeignCurrencyTranslationGainLoss_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Cumulative translation adjustment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PrepaidExpensesAndOtherCurrentAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Prepaid Expenses And Other Current Assets [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PrepaidExpensesAndOtherCurrentAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expenses And Other Current Assets [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PrepaidExpensesAndOtherCurrentAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid Expenses And Other Current Assets [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-Average Exercise Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Decrease for Tax Withholding Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Tax withholding on vesting of restricted stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from (Payments for) Other Financing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DefinedContributionPlanEmployeeEligibilityAge_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Defined Contribution Plan Employee Eligibility Age</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DefinedContributionPlanEmployeeEligibilityAge_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Contribution Plan Employee Eligibility Age</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DefinedContributionPlanEmployeeEligibilityAge_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Defined contribution plan, eligible age of employees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Research and Development Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByBalanceSheetGroupingTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, by Balance Sheet Grouping [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cash and Cash Equivalents [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Tax Liabilities, Gross, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Liabilities, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel">Total deferred tax liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Conversion, Converted Instrument, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total consideration on conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Fair value of 2,316,229 shares of common stock issued for conversion of convertible notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of convertible senior notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Fair value of the note</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Executive Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation Nondeductible Expense Executive Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Executive compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchaseProgramAuthorizedAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share repurchase amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchaseProgramAuthorizedAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchase Program, Authorized Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net proceeds from public offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds from issuance of common stock, net of issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Conversion of Units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Issuance of common stock for debt conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Amortization of Intangible Assets, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Amortization expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Incentive options, vesting period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock, $0.01 par value; 80,000,000 shares authorized; 55,766,078 shares at December 31, 2023 and 55,557,698 shares at December 31, 2022 issued and outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Common Stock, Value, Issued, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Common Stock, Value, Issued, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Common Stock, Value, Issued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Conversion Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Notes initial conversion price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in valuation allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ContingentConsiderationObligationEstimated_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent consideration obligation estimated</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ContingentConsiderationObligationEstimated_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contingent Consideration Obligation Estimated</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ContingentConsiderationObligationEstimated_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contingent Consideration Obligation Estimated</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CashConsiderationExcludingRestrictedCash_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash consideration excluding restricted cash.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CashConsiderationExcludingRestrictedCash_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Consideration Excluding Restricted Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CashConsiderationExcludingRestrictedCash_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNoncashIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Noncash Income (Expense), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNoncashIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Noncash Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNoncashIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringReserve_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restructuring Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringReserve_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring Reserve</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringReserve_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Restructuring Reserve, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringReserve_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Restructuring Reserve, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringReserve_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Restructuring Reserve, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxImpactOnConversionFeature_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax impact on conversion feature</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxImpactOnConversionFeature_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Impact On Conversion Feature</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxImpactOnConversionFeature_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred tax impact on conversion feature.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total accrued liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Share-based Payment Arrangement, Noncash Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Noncash Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AuditorName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Auditor Firm Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AuditorName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Auditor Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentIssuedForCash_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Notes for cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentIssuedForCash_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Issued For Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentIssuedForCash_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument issued for cash.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income from operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition, Equity Interest Issued or Issuable, Number of Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares issued for business acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Shares of common stock issued for acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferred1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Consideration Transferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferred1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business combination, consideration transferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferred1_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Fair value of net assets acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxPeriodAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tax Period [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxPeriodAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax Period [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Income Tax Expense (Benefit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred income taxes, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income tax provision</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Income tax (benefit) provision</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-Average Remaining Contractual Term (in years)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross amounts of decreases in unrecognized tax benefits as a result of tax positions taken in the prior period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gross amounts of decreases in unrecognized tax benefits as a result of tax positions taken in the prior period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ChromatographyProductsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Chromatography Products [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ChromatographyProductsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Chromatography Products [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NatureOfOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nature of Operations [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NatureOfOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Organization and Nature of Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesAcquisitions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Acquisitions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesAcquisitions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of commons stock pursuant to the acquisition, (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Cash_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Cash_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payment of earnout consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of earnout consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment for Contingent Consideration Liability, Financing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForRestructuring_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Amount Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForRestructuring_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments for Restructuring</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RoyaltyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Royalty and Other Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RoyaltyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RoyaltyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Royalty and Other Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskPercentage1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable, percentage by customer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskPercentage1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskPercentage1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Revenue from significant customers as a percentage of total revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FairValueOfEmbeddedConversionOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of embedded conversion option</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FairValueOfEmbeddedConversionOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value of Embedded Conversion Option [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FairValueOfEmbeddedConversionOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Fair value of embedded conversion option.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected volatility (range), maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Indefinite-Lived Intangible Assets [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Indefinite-lived Intangible Assets [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment, Tax Withholding, Share-Based Payment Arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payment of tax withholding obligation on vesting of restricted stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DilutiveSecuritiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Securities, Effect on Basic Earnings Per Share [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DilutiveSecuritiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of dilutive securities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation of Revenue [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Incentive options, vesting percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share-based Compensation Arrangement by Share-based Payment Award, Options, Aggregate Intrinsic Value [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Compensation Arrangement by Share-based Payment Award, Options, Aggregate Intrinsic Value [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToParentDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Numerator for diluted earnings per share - net income available to common stockholders after the effect of dilutive securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToParentDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss) Attributable to Parent, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToParentDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Numerator for diluted earnings per share - net income available to common stockholders after the effect of dilutive securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Operating Lease Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Concentration Risk [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Taxes Payable, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Taxes Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Finite-Lived Intangible Assets, Net, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Finite-Lived Intangible Assets, Net, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NumberOfManufacturingSites_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of manufacturing sites.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NumberOfManufacturingSites_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Manufacturing Sites</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NumberOfManufacturingSites_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of manufacturing sites</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Revenue, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Deferred revenue (included in accrued liabilities and other noncurrent liabilities in the consolidated balance sheets)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxesPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Taxes Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxesPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income tax paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationTechniqueDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation Approach and Technique [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Contract with Customer [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Revenue Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Granted | shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options outstanding at December 31, 2020</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationIndemnificationAssetsRangeOfOutcomesValueHigh_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Indemnification Assets, Range of Outcomes, Value, High</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate principal amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Face Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Principal amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerSharePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerSharePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnings Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in valuation allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross amounts of increases in unrecognized tax benefits as a result of tax positions taken in the current period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ComputerHardwareAndSoftwareMemberMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Computer Hardware And Software Member Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ComputerHardwareAndSoftwareMemberMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Computer Hardware And Software member [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCredits_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Effective Income Tax Rate Reconciliation, Tax Credit, Percent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCredits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCredits_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Business tax credits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income (expenses)</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Nonoperating Income (Expense), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfCashAndCashEquivalentsAndRestrictedCashTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of cash and cash equivalents and restricted cash.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfCashAndCashEquivalentsAndRestrictedCashTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Cash And Cash Equivalents And Restricted Cash [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfCashAndCashEquivalentsAndRestrictedCashTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Schedule of Cash, Cash Equivalents and Restricted Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Noncurrent contingent consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Liability, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveSecuritiesEffectOnBasicEarningsPerShareConvertibleSeniorNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive securities effect on basic earnings per share convertible senior notes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveSecuritiesEffectOnBasicEarningsPerShareConvertibleSeniorNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Securities Effect On Basic Earnings Per Share Convertible Senior Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveSecuritiesEffectOnBasicEarningsPerShareConvertibleSeniorNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Convertible Senior Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Depreciation, Depletion and Amortization, Nonproduction, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation, Depletion and Amortization, Nonproduction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation and amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityVoluntaryFilers_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Voluntary Filers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive income (loss):</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) from Continuing Operations before Income Taxes, Foreign</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfEarningsPerShareBasicAndDilutedTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Earnings Per Share Basic And Diluted [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfEarningsPerShareBasicAndDilutedTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule Of Earnings Per Share Basic And Diluted [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfEarningsPerShareBasicAndDilutedTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Earnings Per Share Basic And Diluted [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilityNonCurrent_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Operating lease liability, long-term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilityNonCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed Operating Lease Liability Non Current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilityNonCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed Operating Lease Liability Non Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilityNonCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating lease liability, long-term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AdditionalUndiscountedInContingentConsiderationEarnoutPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional undiscounted in contingent consideration earnout payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AdditionalUndiscountedInContingentConsiderationEarnoutPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional undiscounted in contingent consideration earnout payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AdditionalUndiscountedInContingentConsiderationEarnoutPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional undiscounted in contingent consideration earnout payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustments due to:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CTechnologiesIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">C Technologies Inc Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CTechnologiesIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">C Technologies Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CTechnologiesIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">C Technologies Inc</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UnrecognizedTaxBenefitsPeriodGrossDecreasesRelease_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unrecognized Tax Benefits, Period Gross Decreases Release</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UnrecognizedTaxBenefitsPeriodGrossDecreasesRelease_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Period Gross Decreases Release</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UnrecognizedTaxBenefitsPeriodGrossDecreasesRelease_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gross amounts of decrease due to release</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other noncurrent assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Assets, Noncurrent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-Based Payment Arrangement, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OtherProductsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other products [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OtherProductsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other products [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders' Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Depreciation, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long term deferred tax liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liability Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liability Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestPaidNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Paid, Excluding Capitalized Interest, Operating Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestPaidNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USTreasuryBillSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">US Treasury Bill Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USTreasuryBillSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">U.S. treasury bills</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TrustForBenefitOfEmployeesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trust for Benefit of Employees [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TrustForBenefitOfEmployeesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetirementPlanTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retirement Plan Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetirementPlanTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Retirement Plan Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vested and expected to vest at December 31, 2022</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Interest Rate Terms</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest repayment terms</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders' equity:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">2029 and thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, after Year Five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCostTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease, Cost [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCostTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Lease, Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCostTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Operating Lease Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOfIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment of intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOfIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Impairment of Intangible Assets (Excluding Goodwill)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOfIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Impairment of Intangible Assets (Excluding Goodwill), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DevelopedTechnologyRightsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Developed Technology Rights [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DevelopedTechnologyRightsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Developed technology</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportingUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of reporting units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportingUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Reporting Units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested in Period, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total fair value of stock options vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cost of Goods and Services Sold, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Goods and Services Sold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of product revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnings per share:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Earnings per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Maturities of Operating Lease Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Indefinite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Indefinite-lived Intangible Assets, Major Class Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Effective Income Tax Rate Reconciliation, Tax Contingency, Amount, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Contingency, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Uncertain tax provisions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Tax Liabilities, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Liabilities, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel">Total net deferred tax liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred Tax Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingPoliciesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Policies [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeaseDescriptionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Lease, Description [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Sweden</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ZeroPointThreeSevenFivePercentageConvertibleSeniorNotesDueTwentyTwentyFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Zero Point Three Seven Five Percentage Convertible Senior Notes Due Twenty Twenty Four Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ZeroPointThreeSevenFivePercentageConvertibleSeniorNotesDueTwentyTwentyFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Zero Point Three Seven Five Percentage Convertible Senior Notes Due Twenty Twenty Four [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ZeroPointThreeSevenFivePercentageConvertibleSeniorNotesDueTwentyTwentyFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">0.375% Convertible Senior Notes due 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Conversion of Units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Issuance of common stock for debt conversion (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk, Credit Risk, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentrations of Credit Risk and Significant Customers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based Compensation Arrangement by Share-based Payment Award [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UnvestedOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unvested Options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UnvestedOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unvested Options [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UnvestedOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unvested Options [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionProFormaInformationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition, Pro Forma Information [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionProFormaInformationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unaudited Supplemental Pro Forma Information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateEffectivePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Interest Rate, Effective Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateEffectivePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effective interest rate on the Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxDeferredExpenseOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Tax Deferred Expense, Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxDeferredExpenseOther_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLeaseNotYetCommencedTermOfContract1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease obligation terms</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLeaseNotYetCommencedTermOfContract1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ManufacturingLineExpansionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Manufacturing Line Expansions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ManufacturingLineExpansionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Manufacturing Line Expansions [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ManufacturingLineExpansionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Manufacturing line expansions.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NumberOfSharesBasicOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of shares basic outstanding.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NumberOfSharesBasicOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Shares Basic Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NumberOfSharesBasicOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted average shares used in computing net income per share - basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Earnings Per Share, Basic, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CustomerConcentrationRiskMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer Concentration Risk [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CustomerConcentrationRiskMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer Concentration Risk</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ProteinsProductsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Protein Products [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ProteinsProductsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proteins Products [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Changes in Accumulated Other Comprehensive Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and contingencies (Note 13)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ProbabilityWeightedPresentValueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Probability Weighted Present Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ProbabilityWeightedPresentValueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Probability-Weighted Present Value [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ProbabilityWeightedPresentValueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Probability-weighted present value.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combinations [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationAcquisitionRelatedCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Acquisition Related Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationAcquisitionRelatedCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business Combination, Acquisition Related Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ZeroPointThreeSevenFivePercentConvertibleSeniorNotesDueTwentyTwentyFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Zero Point Three Seven Five Percent Convertible Senior Notes Due Twenty Twenty Four Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ZeroPointThreeSevenFivePercentConvertibleSeniorNotesDueTwentyTwentyFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Zero Point Three Seven Five Percent Convertible Senior Notes Due Twenty Twenty Four [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ZeroPointThreeSevenFivePercentConvertibleSeniorNotesDueTwentyTwentyFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">0.375% Convertible Senior Notes due 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business acquisition, revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Indefinite-lived Intangible Assets (Excluding Goodwill), Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Indefinite-lived Intangible Assets (Excluding Goodwill), Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Indefinite-lived Intangible Assets (Excluding Goodwill), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Indefinite-Lived Intangible Assets (Excluding Goodwill)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Gross Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetAndLiabilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetAndLiabilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Summary of Receivables and Deferred Revenue from Contracts with Customers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Cost</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest and penalties related to income taxes</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PrepaidExpensesAndOtherCurrentAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Prepaid Expenses And Other Current Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PrepaidExpensesAndOtherCurrentAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expenses And Other Current Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PrepaidExpensesAndOtherCurrentAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid Expenses And Other Current Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CompensationAndRetirementDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retirement Benefits [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FederalAndStateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Federal and State [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FederalAndStateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Federal and State [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FederalAndStateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Federal and State</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringCostAndReserveAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vested and expected to vest at December 31, 2021 | shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Range [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Operating Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total cash provided by operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FairValueOfSharesOfCommonStockIssuedForContingentConsiderationEarnouts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of shares of common stock issued for contingent consideration earnouts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FairValueOfSharesOfCommonStockIssuedForContingentConsiderationEarnouts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value of Shares of Common Stock Issued for Contingent Consideration Earnouts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FairValueOfSharesOfCommonStockIssuedForContingentConsiderationEarnouts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Fair value of shares of common stock issued for contingent consideration earnouts.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationForeignExchangeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign exchange loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationForeignExchangeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Foreign Exchange Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationForeignExchangeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Effective income tax rate reconciliation, foreign exchange loss.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVested_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVested_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate intrinsic value of restricted stock units vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NewtonNewJerseyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Newton, New Jersey [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NewtonNewJerseyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Newton, New Jersey Member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NewtonNewJerseyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">NTM</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Range [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Accounts Receivable, Allowance for Credit Loss, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Accounts Receivable, Allowance for Credit Loss, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, Allowance for Credit Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodEndLabel">Ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodStartLabel">Beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfAccruedLiabilitiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Accrued Liabilities [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfAccruedLiabilitiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Accrued Liabilities [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfAccruedLiabilitiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Accrued Liabilities [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasePayments_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Operating lease cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Earnings Per Share, Diluted, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductsAndServicesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfSalesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Sales [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfSalesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of product revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Tax Assets, Operating Loss Carryforwards, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Operating Loss Carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net operating loss carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance of gross unrecognized tax benefits, end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance of gross unrecognized tax benefits, beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ExchangedTwoZeroOneNineNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exchanged 2019 Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ExchangedTwoZeroOneNineNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Exchanged Two Zero One Nine Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ExchangedTwoZeroOneNineNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Exchanged two zero one nine notes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskBenchmarkDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Benchmark [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskBenchmarkDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentration Risk Benchmark [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BuildingsAndImprovementsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Buildings and Improvements, Gross, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BuildingsAndImprovementsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Buildings and Improvements, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BuildingsAndImprovementsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Buildings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OpenTaxYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Open Tax Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OpenTaxYear_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Fiscal year subject to examination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options exercisable at December 31, 2023 | shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Noncurrent Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Recurring</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Recurring [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_APACOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">APAC/Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_APACOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">A P A C Other [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_APACOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">APAC Other [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Additional Paid in Capital, Common Stock, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Additional Paid in Capital, Common Stock, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid in Capital, Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional paid-in capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationConsiderationIndemnificationEscrow_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business Combination Consideration Indemnification Escrow</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationConsiderationIndemnificationEscrow_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Consideration Indemnification Escrow</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationConsiderationIndemnificationEscrow_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business acquisition, Indemnification escrow</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Policy [Policy Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PensionPlansDefinedBenefitMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Pension Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PensionPlansDefinedBenefitMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pension Plans, Defined Benefit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Translation adjustment</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FurnitureFixturesAndOfficeEquipmentMemberMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Furniture Fixtures And Office Equipment Member Member</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TaxYear2043Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tax Year 2043 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NonEmployeeDirectorStockOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Non Employee Director Stock Option[Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CommitmentsAndContingenciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitments and Contingencies [Table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherPostretirementBenefitsIndividualContractsTypeOfDeferredCompensationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Postretirement Benefits, Individual Contracts, Type of Deferred Compensation [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditLossFinancialInstrumentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Loss, Financial Instrument [Policy Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercised number of shares</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Other Adjustments, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maturity of one year or less, Estimated Fair Value</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ProvisionForDeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Provision for Deferred Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ProvisionForDeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DaylightSolutionsIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Daylight solutions Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DaylightSolutionsIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Daylight Solutions Inc.[Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DaylightSolutionsIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Daylight Solutions Inc.[Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AcceleratedDepreciationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accelerated depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AcceleratedDepreciationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accelerated Depreciation [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AcceleratedDepreciationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accelerated depreciation.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueAcquisitions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Acquisitions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueAcquisitions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of commons stock pursuant to the acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PolymemSAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Polymem S.A.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PolymemSAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Polymem S.A. [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PolymemSAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Polymem S.A. [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionRatio1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Conversion Ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionRatio1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Notes conversion ratio per $1,000 principal amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Private Placement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Private Placement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentConvertibleIntoEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument convertible into equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentConvertibleIntoEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Convertible Into Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentConvertibleIntoEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument amount convertible into equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsidiary, Ownership Percentage, Noncontrolling Owner</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non controlling ownership interest minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Fair value of shares of common stock issued for acquisitions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Threshold Consecutive Trading Days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Notes threshold consecutive trading days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits that Would Impact Effective Tax Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impact of unrecognized tax benefits on effective tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Accounts Payable, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accounts Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LatestTaxYearMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Latest Tax Year [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LatestTaxYearMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Latest Tax Year</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OutstandingTwoZeroTwoThreeNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Outstanding two zero two three notes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TextBlockAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Text Block [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, Undiscounted Excess Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Less amount of lease payment representing interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less amount of lease payment representing interest</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares Awarded</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FiniteLivedIntangibleLiabilitiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Finite-Lived Intangible Liabilities [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FiniteLivedIntangibleLiabilitiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite Lived Intangible Liabilities [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FiniteLivedIntangibleLiabilitiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finite-Lived Intangible Liabilities [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FiniteLivedIntangibleLiabilitiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Finite-Lived Intangible Liabilities [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityWellKnownSeasonedIssuer_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Well-known Seasoned Issuer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition, Pro Forma Net Income (Loss)</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercised</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasicAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Basic [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NGLImpactAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">NGL Impact A[Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AvitideIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Avitide, Inc. [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cash consideration</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NoncashInventoryAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non cash inventory adjustment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NoncashInventoryAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Noncash Inventory Adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NoncashInventoryAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">The amount of non cash adjustments of inventory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SummaryOfSignificantAccountingPoliciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary Of Significant Accounting Policies [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SummaryOfSignificantAccountingPoliciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary Of Significant Accounting Policies [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SummaryOfSignificantAccountingPoliciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary Of Significant Accounting Policies [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average, Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LocalPhoneNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Local Phone Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant and Equipment [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options exercisable at December 31, 2023</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationAdditionalCashForTransactionBonus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Additional Cash For Transaction Bonus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationAdditionalCashForTransactionBonus_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination additional cash for transaction bonus.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedTangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Tangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedTangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Tangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedTangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of tangible assets acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Goodwill, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxAssetsOperatingLeases_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Tax Assets Operating Leases.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxAssetsOperatingLeases_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets Operating Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxAssetsOperatingLeases_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfCashFlowsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Cash Flows [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OperatingLeaseLiabilitiesExcludingControlNotConveyedLeases_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Minimum operating lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OperatingLeaseLiabilitiesExcludingControlNotConveyedLeases_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liabilities excluding control not conveyed leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OperatingLeaseLiabilitiesExcludingControlNotConveyedLeases_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease Liabilities Excluding Control not Conveyed Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OperatingLeaseLiabilitiesExcludingControlNotConveyedLeases_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Operating lease liabilities excluding control not conveyed leases.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarliestTaxYearMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earliest Tax Year [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarliestTaxYearMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earliest Tax Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationLossOnDebtExchangePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss on extinguishment of debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationLossOnDebtExchangePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Loss on Debt Exchange, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationLossOnDebtExchangePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Effective income tax rate reconciliation, loss on debt exchange, percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationsCashDepositedInEscrowAccount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combinations cash deposited in escrow account.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationsCashDepositedInEscrowAccount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combinations Cash Deposited In Escrow Account</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationsCashDepositedInEscrowAccount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business combinations cash deposited in escrow account</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EngineeredMoldingTechnologyLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Engineered Molding Technology LLC</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EngineeredMoldingTechnologyLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Engineered Molding Technology LLC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EngineeredMoldingTechnologyLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Engineered Molding Technology LLC</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Authority [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Tax Authority [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accumulated Other Comprehensive Income (Loss), Net of Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss), Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated other comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant &amp; Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedTranslationAdjustmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Foreign Currency Adjustment Attributable to Parent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedTranslationAdjustmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Foreign Currency Translation Adjustment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskByBenchmarkAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Benchmark [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskByBenchmarkAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentration Risk Benchmark [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentAnnualReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Annual Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrincipalOwnerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Principal Owner [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrincipalOwnerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Principal Owner</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TonyJHuntMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tony J. Hunt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TonyJHuntMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tony J. Hunt [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TonyJHuntMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tony J. Hunt.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of exchange rate changes on cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss) Available to Common Stockholders, Basic [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Numerator:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ConvertibleNotesTransactionCostsOfEquityComponent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible notes transaction costs of equity component.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ConvertibleNotesTransactionCostsOfEquityComponent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Notes Transaction Costs Of Equity Component</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ConvertibleNotesTransactionCostsOfEquityComponent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Transaction costs attributable to equity component</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_InflationReductionActOfTwoThousandTwentyTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Inflation reduction act of two thousand twenty two member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_InflationReductionActOfTwoThousandTwentyTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inflation Reduction Act Of Two Thousand Twenty Two [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_InflationReductionActOfTwoThousandTwentyTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">nflation Reduction Act Of Two Thousand Twenty Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Interest Rate, Stated Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Notes, interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Senior convertible notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrecognized compensation cost, weighted average remaining requisite service period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Lived Tangible Asset [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vested and expected to vest at December 31, 2021</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Percent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustments due to:</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total convertible senior notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Senior Notes due 2028, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Debt, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationDebtDiscountPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt discount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationDebtDiscountPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation Debt Discount Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationDebtDiscountPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Effective income tax rate reconciliation debt discount percentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractualObligationDueInNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contractual Obligation, to be Paid, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractualObligationDueInNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Outstanding obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OnePointZeroZeroPercentConvertibleSeniorNotesDueTwentyTwentyEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">1.00% Convertible Senior Notes due 2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OnePointZeroZeroPercentConvertibleSeniorNotesDueTwentyTwentyEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">One Point Zero Zero Percent Convertible Senior Notes Due Twenty Twenty Eight [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OnePointZeroZeroPercentConvertibleSeniorNotesDueTwentyTwentyEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">One point zero zero percent convertible senior notes due twenty twenty eight.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdTradingDays_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Threshold Trading Days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdTradingDays_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Notes threshold trading days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCredits_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Effective Income Tax Rate Reconciliation, Tax Credit, Amount, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCredits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCredits_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Business tax credits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Operating lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed Operating Lease Liability Current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed Operating Lease Liability Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentIncreaseAccruedInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Increase, Accrued Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentIncreaseAccruedInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accrued interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level 3</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 3 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">APIC, Share-based Payment Arrangement, Increase for Cost Recognition, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">APIC, Share-Based Payment Arrangement, Increase for Cost Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Recurring and Nonrecurring [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermDebtTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-Term Debt, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_OwnershipDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Ownership [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net increase (decrease) in cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Carrying Amount of Equity Component</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Equity component of converted debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryWorkInProcessNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Work in Process, Net of Reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryWorkInProcessNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Work-in-process</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PayablesAndAccrualsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payables and Accruals [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total noncurrent assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForProceedsFromOtherInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments for (Proceeds from) Other Investing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForProceedsFromOtherInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForProceedsFromOtherInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsGrossExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Gross Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsGrossExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Assets, Gross (Excluding Goodwill)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsGrossExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BioflexMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">BioFlex [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BioflexMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">BioFlex [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BioflexMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">BioFlex</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NoncashInterestIncome_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Non-cash interest income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NoncashInterestIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Noncash Interest Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NoncashInterestIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Noncash interest income.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetirementPlanSponsorLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retirement Plan Sponsor Location [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFinStmtErrorCorrectionFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Financial Statement Error Correction [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFinStmtErrorCorrectionFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Financial Statement Error Correction [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfAccruedLiabilitiesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Accrued Liabilities [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfAccruedLiabilitiesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Accrued Liabilities [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfAccruedLiabilitiesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Accrued Liabilities [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInventoryCurrentTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Inventory, Current [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInventoryCurrentTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Inventories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfDeferredTaxAssetsAndLiabilitiesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Deferred Tax Assets and Liabilities [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfDeferredTaxAssetsAndLiabilitiesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Deferred Tax Assets and Liabilities [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfDeferredTaxAssetsAndLiabilitiesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Deferred Tax Assets and Liabilities [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditLossAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Loss [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SummaryOfIncomeTaxExaminationsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary of Income Tax Examinations [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SummaryOfIncomeTaxExaminationsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Tax Returns Periods Subject to Examination by Federal, State and Foreign Tax Authorities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventories, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total inventories, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PostemploymentBenefitsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Postemployment Benefits [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from operating activities:</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AcquiredFiniteLivedIntangibleAssetResidualValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Intangible Asset Residual Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Quarterly Financial Information [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Consolidated Statements of Operations Information for Each of Previous Eight Quarters</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unvested at December 31, 2020</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FacilityAndOtherExitCostsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Facility and other exit costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FacilityAndOtherExitCostsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Facility and Other Exit Costs [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FacilityAndOtherExitCostsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Facility and other exit costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition [Line Items]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_NameOfMajorCustomerDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_NameOfMajorCustomerDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Total</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less - Accumulated depreciation</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted average shares used in computing net income per share - basic</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationOtherReconcilingItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationOtherReconcilingItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRestructuringAndRelatedCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Activity Related to Restructuring Plan</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignIncomeTaxExpenseBenefitContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Income Tax Expense (Benefit), Continuing Operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignIncomeTaxExpenseBenefitContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Restricted Stock Unit Activity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Loss on extinguishment of debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss on extinguishment of debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Loss on conversion of debt</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss) on Extinguishment of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MeasurementInputRevenueVolumeDiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue and Volume Based Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MeasurementInputRevenueVolumeDiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Measurement Input Revenue &amp; Volume Discount Rate.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MeasurementInputRevenueVolumeDiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Revenue &amp; Volume Discount Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MeasurementInputProbabilityOfSuccessMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Probability of Success</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MeasurementInputProbabilityOfSuccessMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Measurement Input Probability of Success.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MeasurementInputProbabilityOfSuccessMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Probability of Success [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestOutstandingWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average, Vested and expected to vest at December 31, 2023</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestOutstandingWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share based compensation arrangement by share based payment award equity instruments other than options vested and expected to vest outstanding weighted average grant date fair value.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestOutstandingWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Based Compensation Arrangement by Share Based Payment Award Equity Instruments Other Than Options Vested and Expected to Vest Outstanding Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Option, Activity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Option Activity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Related Party Transactions, by Related Party [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Related Party [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContingentConsiderationTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contingent Consideration Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContingentConsiderationTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent Consideration Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated Weighted Average Assumptions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveEffectOnSharesOfConversionPremium_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Dilutive effect on shares of conversion premium</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveEffectOnSharesOfConversionPremium_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Effect On Shares Of Conversion Premium</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveEffectOnSharesOfConversionPremium_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive effect on shares of conversion premium.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total future minimum lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total noncurrent liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ExchangeTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exchange Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ExchangeTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Exchange Transaction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ExchangeTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Exchange Transaction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PrepaidServicesAndProfessionalFees_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Prepaid Services and Professional Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PrepaidServicesAndProfessionalFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Services and Professional Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PrepaidServicesAndProfessionalFees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equipment maintenance and services</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transactions Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party Transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationLossOnDebtExchange_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss on extinguishment of debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationLossOnDebtExchange_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Loss on Debt Exchange</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationLossOnDebtExchange_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Effective income tax rate reconciliation, loss on debt exchange.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Fair value of net assets acquired</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of net assets acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Debt [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Carrying Value of Convertible Senior Notes</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ModificationOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Modification of debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ModificationOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Modification of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ModificationOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Modification of debt.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromCurrentPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrecognized tax benefits decreases resulting from current period tax positions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromCurrentPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Decrease Resulting from Current Period Tax Positions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed Operating Lease Right Of Use Asset.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed Operating Lease Right Of Use Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating lease right of use asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEntityWideDisclosureOnGeographicAreasLongLivedAssetsInIndividualForeignCountriesByCountryTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country [Table Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease, Cost</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RoyaltyExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty Expense</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable, net of reserves of $2,122 and $1,365 at December 31, 2023 and December 31, 2022, respectively</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accounts Receivable, after Allowance for Credit Loss, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, after Allowance for Credit Loss, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accounts receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_VariableOperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for operating leases.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_VariableOperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Variable Operating Lease cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_VariableOperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Variable operating lease cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MajorCustomersAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MajorCustomersAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer [Axis]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxLiabilitiesOperatingLeaseRightOfUseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Liabilities, Operating Lease Right Of Use Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxLiabilitiesOperatingLeaseRightOfUseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease right of use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesHeldToMaturityAndCashAndCashEquivalentsEstimatedFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt securities held to maturity and cash and cash equivalents estimated fair value.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesHeldToMaturityAndCashAndCashEquivalentsEstimatedFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities Held to Maturity and Cash and Cash Equivalents Estimated Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesHeldToMaturityAndCashAndCashEquivalentsEstimatedFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents, Estimated Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockIssuedDuringPeriodValueContingentConsiderationEarnoutPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock pursuant to the Avitide, Inc. contingent consideration earnout payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockIssuedDuringPeriodValueContingentConsiderationEarnoutPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value,Contingent Consideration Earnout Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockIssuedDuringPeriodValueContingentConsiderationEarnoutPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock issued during period, value,contingent consideration earnout payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AcquisitionDateFairValueOfContingentConsiderationEarnouts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquisition date fair value of contingent consideration earnouts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AcquisitionDateFairValueOfContingentConsiderationEarnouts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Acquisition Date Fair Value of Contingent Consideration Earnouts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AcquisitionDateFairValueOfContingentConsiderationEarnouts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Acquisition date fair value of contingent consideration earnouts.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConstructionInProgressGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Construction in Progress, Gross</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash and Cash Equivalents, at Carrying Value, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash and Cash Equivalents, at Carrying Value, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash and Cash Equivalents, at Carrying Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents, at Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cash and cash equivalents</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RevenueAndVolumeProjectionsPerformancePeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revenue and volume projections performance period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RevenueAndVolumeProjectionsPerformancePeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue And Volume Projections Performance Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RevenueAndVolumeProjectionsPerformancePeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Performance period</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-Based Compensation Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options exercisable at December 31, 2021</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BuildingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Building [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExaminationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Examination [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExaminationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Tax Examination [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TradeAccountsReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trade Accounts Receivable Member</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ExchangeAndSubscriptionAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exchange and Subscription Agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ExchangeAndSubscriptionAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Exchange and Subscription Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ExchangeAndSubscriptionAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Exchange and subscription agreements.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasedAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Leased Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) from Continuing Operations before Income Taxes, Domestic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Domestic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Convertible note modification</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of Convertible Securities Stock Issued | value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TrueUpCostsDecember2020Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">True Up Costs December 2020</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TrueUpCostsDecember2020Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">True up costs December 2020.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TrueUpCostsDecember2020Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">True up costs December 2020 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfessionalFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Professional Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfessionalFees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Spectrum Acquisition, tax preparation and other fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_InventoryAdjustmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_InventoryAdjustmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Adjustments [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_InventoryAdjustmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Inventory adjustments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cover [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Selling, general and administrative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermPurchaseCommitmentCategoryOfItemPurchasedDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Purchase Commitment, Category of Item Purchased [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonrecurringAdjustmentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nonrecurring Adjustment [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VestingAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Vesting [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VestingAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vesting [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Year Focus</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxLiabilitiesDebtDiscount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Liabilities, Debt discount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxLiabilitiesDebtDiscount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred tax liabilities, debt discount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxesPaidNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income Taxes Paid, Net, Total</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StateAndLocalIncomeTaxExpenseBenefitContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">State</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Policy Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PatentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Patents [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Security Exchange Name</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DomesticCountryMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Domestic Tax Authority [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DomesticCountryMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Domestic Tax Authority</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Schedule of Amortization Expense for Amortized Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive loss</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CustomerRelationshipsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer Relationships [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CustomerRelationshipsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer relationships</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Finite-Lived Intangible Assets [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Finite-Lived Intangible Assets [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SpectrumIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Spectrum Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SpectrumIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Spectrum Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SpectrumIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Spectrum Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SpectrumIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Spectrum Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Property, Plant and Equipment, Gross, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Property, Plant and Equipment, Gross, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total property, plant and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets acquired under operating leases</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LegalEntityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Legal Entity [Axis]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average common shares outstanding:</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from issuance of 2023 Convertible Senior Notes</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate intrinsic value of stock options exercised</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Flag</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewDateOfAnnualGoodwillImpairmentTest_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment assessment date</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capital Units [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Capital Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditLossFinancialInstrumentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Loss, Financial Instrument [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditLossFinancialInstrumentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncreaseDecreaseInOperatingLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represents Increase Decrease In operating Lease Liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncreaseDecreaseInOperatingLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease In Operating Lease Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncreaseDecreaseInOperatingLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase in operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeasesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leases [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029 and thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, after Year Five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncomeTaxReconciliationNondeductibleExpenseExecutiveCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Income Tax Reconciliation, Nondeductible Expense, Executive Compensation.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncomeTaxReconciliationNondeductibleExpenseExecutiveCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Reconciliation Nondeductible Expense Executive Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncomeTaxReconciliationNondeductibleExpenseExecutiveCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Executive compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationFdiiPercent_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Foreign-derived intangible income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationFdiiPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign-derived intangible income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationFdiiPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, FDII, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MilliporeSigmaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Millipore Sigma.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MilliporeSigmaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Millipore Sigma [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MilliporeSigmaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">MilliporeSigma</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Accrued Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Accrued Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accrued liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxPeriodDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tax Period [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxPeriodDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax Period [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRestructuringReserveByTypeOfCostTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Restructuring Activities by Type of Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRestructuringReserveByTypeOfCostTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Restructuring Reserve by Type of Cost [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Securities Act File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OptionToPurchaseCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Option To Purchase Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OptionToPurchaseCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Option To Purchase Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OptionToPurchaseCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Option To Purchase Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RisksAndUncertaintiesInEntitiesBusinessPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Risks and Uncertainties in Entities Business [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RisksAndUncertaintiesInEntitiesBusinessPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Risks and Uncertainties in Entities Business [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RisksAndUncertaintiesInEntitiesBusinessPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Risks and Uncertainties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRevenueByMajorCustomersByReportingSegmentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRevenueByMajorCustomersByReportingSegmentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of Revenue from Significant Customers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total deferred tax assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill and Intangible Assets Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill and Other Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Goodwill and Other Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxEffectsAllocatedDirectlyToEquityEquityTransactions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Effects Allocated Directly to Equity, Equity Transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxEffectsAllocatedDirectlyToEquityEquityTransactions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash and cash equivalents, beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total cash, cash equivalents, and restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash and cash equivalents, end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_WeightedAverageDiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Discount Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_WeightedAverageDiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted average discount rate.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_WeightedAverageDiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Discount Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net liabilities assumed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accounts Payable, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AbstractOfOperatingLeaseLiabilityFromBalanceSheetTableTextBlockTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">na</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AbstractOfOperatingLeaseLiabilityFromBalanceSheetTableTextBlockTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Abstract Of Operating Lease Liability From Balance Sheet Table Text Block [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AbstractOfOperatingLeaseLiabilityFromBalanceSheetTableTextBlockTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Operating Lease Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Weighted Average, Unvested at December 31, 2023</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Weighted Average, Unvested at December 31,2022</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CommonStockIssuePricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common stock issue price per share.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CommonStockIssuePricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock Issue Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CommonStockIssuePricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock issue price per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Tax Assets, Valuation Allowance, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Valuation Allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less: valuation allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationDebtDiscount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt discount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationDebtDiscount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation Debt discount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationDebtDiscount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Effective income tax ratereconciliation debt discount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostsAndExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Costs and Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostsAndExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total costs and operating expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SchedulesOfConcentrationOfRiskByRiskFactorTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedules of Concentration of Risk, by Risk Factor [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SchedulesOfConcentrationOfRiskByRiskFactorTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage by Geographic Area or Significant Customers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AuditorLocation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Auditor Firm Location</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AuditorLocation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Auditor Location</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected term (in years)</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Preferred Stock, Value, Issued, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Preferred Stock, Value, Issued, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Preferred Stock, Value, Issued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Smaller reporting company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Shell Company</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationReturnToProvisionAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation Return to Provision Adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationReturnToProvisionAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Return to provision adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_LongTermContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Long-term contingent consideration.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_LongTermContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long Term Contingent Consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_LongTermContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term contingent consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition, Transaction Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax withholding on vesting of restricted stock (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Tax withholding on vesting of restricted stock (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DefinedContribution401KPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Defined Contribution 401 K Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DefinedContribution401KPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Contribution 401 K Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DefinedContribution401KPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Defined Contribution 401 K Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExaminationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Examination [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExaminationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Tax Examination [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenuesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenues [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenuesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel">Forfeited/expired/cancelled | Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Forfeited/expired/cancelled | Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TrademarksAndTradeNamesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trademarks and Trade Names [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TrademarksAndTradeNamesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Trademark and tradename</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PuroliteMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purolite</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PuroliteMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Purolite [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PuroliteMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Purolite member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SalesRevenueNetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue Benchmark [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SalesRevenueNetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sales Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInContractWithCustomerAssetAndLiabilityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Revenue recognized during periods presented relating to:</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of acquired finite lived intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Business combination, intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CashAndMoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash and money market funds.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CashAndMoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Money Market Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CashAndMoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and money market funds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualPostretirementBenefitsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Deferred Compensation Arrangement with Individual, Postretirement Benefits [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualPostretirementBenefitsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Deferred Compensation Arrangement with Individual, Postretirement Benefits [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputPriceVolatilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Volatility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputPriceVolatilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input, Price Volatility [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SupplementalBalanceSheetDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Supplemental Balance Sheet Disclosures [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SupplementalBalanceSheetDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Consolidated Balance Sheet Detail</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PercentageOfSharesSubjectToForfeiture_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of shares subject to forfeiture.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PercentageOfSharesSubjectToForfeiture_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage of Shares Subject to Forfeiture</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PercentageOfSharesSubjectToForfeiture_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated forfeiture rates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Finite-Lived Intangible Assets, Gross, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateDuringPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Premium over sale price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateDuringPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Interest Rate During Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MonteCarloSimulationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Monte Carlo Simulation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MonteCarloSimulationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Monte Carlo Simulation.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MonteCarloSimulationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Monte Carlo Simulation [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentArrangementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Arrangement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TrdArrExpirationDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expiration Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TrdArrExpirationDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trd Arr Expiration Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TrdArrExpirationDate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Trd Arr expiration date.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Goodwill [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from issuance of common stock,issuance costs</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Risk-free interest rate, minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement Location [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Statement Location [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationTransactionCostPaidDuringPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Transaction Cost Paid During Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationTransactionCostPaidDuringPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination transaction cost paid during period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfPropertyAndEquipmentUsefulLivesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule Of Property And Equipment Useful Lives Table [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfPropertyAndEquipmentUsefulLivesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Property And Equipment Useful Lives [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfPropertyAndEquipmentUsefulLivesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsInventory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Inventory</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Risk-free interest rate, maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_HeldToMaturitySecuritiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_HeldToMaturitySecuritiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Marketable securities held to maturity</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AvitideLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Avitide Llc</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AvitideLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Avitide LLC.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationFdiiAmount_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Foreign-derived intangible income</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected dividend yield</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PercentageOfCurrentFederalTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage Of Current Federal Tax Expense Benefit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PercentageOfCurrentFederalTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Current Federal Tax Expense Benefit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PercentageOfCurrentFederalTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of alternative minimum tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidInsurance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Insurance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidInsurance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid insurance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RgenFacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Rgen Facility [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RgenFacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Rgen Facility [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Facility Axis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Facility [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AvitideAndFlexbiosysMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Avitide and Flexbiosys</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AvitideAndFlexbiosysMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Avitide and FlexBiosys [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AvitideAndFlexbiosysMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Avitide and FlexBiosys.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFrequencyOfPeriodicPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Frequency of Periodic Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFrequencyOfPeriodicPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Notes, frequency of periodic payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Products</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesHeldToMaturityAndCashAndCashEquivalentsAmortizedCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash and cash equivalents, Amortized Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesHeldToMaturityAndCashAndCashEquivalentsAmortizedCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt securities held to maturity and cash and cash equivalents amortized costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesHeldToMaturityAndCashAndCashEquivalentsAmortizedCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities Held to Maturity and Cash and Cash Equivalents Amortized Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtSecuritiesHeldToMaturityAndCashAndCashEquivalentsAmortizedCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents, Amortized Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Closing price of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current contingent consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Principal amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductOrServiceAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockValueAcquiredCostMethod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Treasury Stock, Value, Acquired, Cost Method</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockValueAcquiredCostMethod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase of treasury stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">State income tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of stock options and vesting of stock units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AvailableForSaleSecuritiesEstimatedFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Available for sale securities estimated fair value.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AvailableForSaleSecuritiesEstimatedFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Available for Sale Securities Estimated Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AvailableForSaleSecuritiesEstimatedFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Marketable securities, Estimated Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UncategorizedAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Uncategorized [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_UncategorizedAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Uncategorized [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_LeaseObligationsNotYetCommenced_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease obligations not yet commenced</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_LeaseObligationsNotYetCommenced_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease Obligations Not Yet Commenced</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_LeaseObligationsNotYetCommenced_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lease obligations not yet commenced.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ProcessAnalyticsProductsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Process Analytics Products Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ProcessAnalyticsProductsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Process Analytics Products [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentTypeCategorizationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investments [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustments for New Accounting Pronouncements [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_QuarterlyFinancialInformationDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Quarterly Financial Information Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income (expenses):</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Nonoperating Income (Expense) [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Notes threshold percentage of stock price trigger</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from External Customers by Products and Services [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockholdersEquityNoteDisclosureTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stockholders Equity Note Disclosure [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockholdersEquityNoteDisclosureTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders Equity Note Disclosure [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockholdersEquityNoteDisclosureTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders Equity Note Disclosure [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TrademarksMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trademarks</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TrademarksMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trademarks [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Investing Activities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from investing activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of debt discount and issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Debt Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StateAndLocalJurisdictionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">State and Local Jurisdiction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StateAndLocalJurisdictionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">State</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ShortTermContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Short-term contingent consideration.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ShortTermContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short Term Contingent Consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ShortTermContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term contingent consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillImpairmentLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment to goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillImpairmentLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill, Impairment Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Reporting</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Diluted, Adjustment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Dilutive potential common shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Dilutive potential common shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Dilutive potential common shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherInformationPertainingToIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Information Pertaining to Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherInformationPertainingToIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net operating loss and business tax credit carry forwards expiration date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskTable_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Concentration Risk [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Lived Tangible Asset [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash, Cash Equivalents and Restricted Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfBusinessCombinationConsiderationTransferredTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tabular disclosure of business combination consideration transferred.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfBusinessCombinationConsiderationTransferredTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Business Combination Consideration Transferred [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfBusinessCombinationConsiderationTransferredTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Business Combination Consideration Transferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Inventories, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Inventories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Inventories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContingentConsiderationByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contingent Consideration by Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContingentConsiderationByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent Consideration by Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Contract with Customer, Liability, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Liabilities, Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Acquired intangible assets</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AccruedLiabilitiesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued Liabilities, Policy [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AccruedLiabilitiesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Liabilities [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AccruedLiabilitiesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued Liabilities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares outstanding</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsNonvestedNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Compensation Arrangement by Share-based Payment Award, Options and Equity Instruments Other Than Options, Nonvested, Number of Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsNonvestedNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of unvested options and restricted stock units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average, Forfeited/Cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restructuring Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Restructuring Costs, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxLiabilitiesConversionOptionOnConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Tax Liabilities, Conversion Option on Convertible Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxLiabilitiesConversionOptionOnConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Liabilities, Conversion Option on Convertible Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DeferredTaxLiabilitiesConversionOptionOnConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Conversion option on convertible notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SupplementalCashFlowElementsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Supplemental Cash Flow Elements [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseContingentConsiderationAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Contingent consideration,Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseContingentConsiderationAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EarnoutConsiderationEarned_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout consideration earned</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EarnoutConsiderationEarned_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout Consideration Earned</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EarnoutConsiderationEarned_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout consideration earned.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetirementPlanTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retirement Plan Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetirementPlanTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Retirement Plan Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentration Risk Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement Location [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Statement Location [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationAndAssetAcquisitionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination and Asset Acquisition [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CashAndCashEquivalentsAndMoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash and cash equivalents And money market funds.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CashAndCashEquivalentsAndMoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash And Cash Equivalents And Money Market Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CashAndCashEquivalentsAndMoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash equivalents and marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Conversion of Convertible Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Conversion of Convertible Securities Stock Issued | shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate202006Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update 2020-06 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate202006Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounting Standards Update 2020-06</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ContingentConsiderationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contingent Consideration Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ContingentConsiderationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contingent consideration expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ContingentConsiderationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Contingent consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_OwnershipAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Ownership [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryCurrentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Current [Table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfDeferredTaxAssetsAndLiabilitiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Deferred Tax Assets and Liabilities [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfDeferredTaxAssetsAndLiabilitiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Deferred Tax Assets and Liabilities [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfDeferredTaxAssetsAndLiabilitiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Deferred Tax Assets and Liabilities [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RepurchaseAgreementCounterpartyNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill and Intangible Assets Disclosure [Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfEarningsPerShareBasicAndDilutedLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule Of Earnings Per Share Basic And Diluted [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfEarningsPerShareBasicAndDilutedLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Earnings Per Share Basic And Diluted [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfEarningsPerShareBasicAndDilutedLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Earnings Per Share Basic And Diluted [Line Items]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Shares, Forfeited/cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total cash provided by (used in) financing activities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPeriodDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Redemption, Period [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Filer Category</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RestrictedStockAndPerformanceStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock And Performance Stock Units [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RestrictedStockAndPerformanceStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restricted stock units and performance stock units.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BalanceSheetLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Balance Sheet Location [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncomeTaxRateReconciliationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Rate Reconciliation [Table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockIssuedDuringPeriodSharesContingentConsiderationEarnoutPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock Issued During Period, shares,contingent consideration earnout payments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, Allowance for Credit Loss, Writeoff</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current period change for write-offs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TradeNamesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trade Names [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TradeNamesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trademark and tradename [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByAssetClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Class [Axis]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business tax credit carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NoncompeteAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Noncompete Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NoncompeteAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Non-compete agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NoncompeteAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-competition agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RgenFacilityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Rgen Facility [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Difference between U.S. and foreign tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted Average Useful Life (in years)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockholdersEquityNoteDisclosureLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stockholders Equity Note Disclosure [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockholdersEquityNoteDisclosureLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders Equity Note Disclosure [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockholdersEquityNoteDisclosureLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders Equity Note Disclosure [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentsIncorporatedByReferenceTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Documents Incorporated by Reference</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentsIncorporatedByReferenceTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Documents Incorporated by Reference [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net Carrying Value</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net income</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Interest expense</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_Rule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Rule 10b5 1 Arr modified flag.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TaxYear2040Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tax Year 2040.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TaxYear2040Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tax Year 2040 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TaxYear2040Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax Year 2040</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">State income and franchise tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CompensationExpenseExcludingCostOfGoodAndServiceSold_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Compensation Expense, Excluding Cost of Good and Service Sold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AreaOfLand_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Area of Land</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AreaOfLand_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Area Of Land</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Measurement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireHeldToMaturitySecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Held-to-Maturity Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireHeldToMaturitySecurities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchase of marketable securities held to maturity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of stock options and vesting of stock units (in shares)</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Diluted</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TaxYearTwoThousandThirtySevenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax Year 2037</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TaxYearTwoThousandThirtySevenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tax Year Two Thousand Thirty Seven [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TaxYearTwoThousandThirtySevenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tax year 2037.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Contingency, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Uncertain tax provisions</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reconciliation of Federal Statutory Rate to Effective Income Tax Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income tax provision</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Weighted Average Remaining Lease Term</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPricePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Notes redemption price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SummaryOfPositionsForWhichSignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary of Positions for which Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SummaryOfPositionsForWhichSignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reconciliation of Unrecognized Tax Benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UseOfEstimates_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Use of Estimates, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UseOfEstimates_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Use of Estimates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net asset acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ContingentConsiderationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent Consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ContingentConsiderationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contingent consideration.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ContingentConsiderationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contingent Consideration [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsNetAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Net [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsNetAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax assets:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_LossOnDebtConversion_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss on conversion of debt included in other expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_LossOnDebtConversion_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loss On Debt Conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_LossOnDebtConversion_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loss on debt conversion.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Options outstanding at December 31, 2023</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Options outstanding at December 31, 2022</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock options, weighted average exercise price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentFaceAmountInCash_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument Face Amount in Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentFaceAmountInCash_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Face Amount in Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentFaceAmountInCash_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt Instrument Face Amount in Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesRestrictedStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares, Restricted Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesRestrictedStock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Options and stock units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reconciliation of Basic and Diluted Shares Amounts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebtExcludingAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Debt, Excluding Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebtExcludingAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contractual coupon interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationTechniqueAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation Approach and Technique [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation of Revenue [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Disaggregation of Revenue [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseholdImprovementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leasehold Improvements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Authority [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Tax Authority [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SubscriptionTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subscription Transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SubscriptionTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subscription Transactions [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SubscriptionTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Subscription transactions.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CommitmentsAndContingenciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitments and Contingencies [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CommitmentsAndContingenciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_CommitmentsAndContingenciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and Contingencies [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Disclosures [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostsAndExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Costs and Expenses [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostsAndExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Costs and operating expenses:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RevenueAndVolumeDiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue and volume discount rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RevenueAndVolumeDiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revenue and volume discount rate.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RevenueAndVolumeDiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue and Volume Discount Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RevenueAndVolumeBasedPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue and Volume Based Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RevenueAndVolumeBasedPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revenue and volume based payments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RevenueAndVolumeBasedPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue and Volume Based Payments [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Current Income Tax Expense (Benefit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FurnitureAndFixturesGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Furniture and Fixtures, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FurnitureAndFixturesGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Furniture, fixtures and office equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfDiscountRateAndLeaseTermUsedInCalculatingLeaseLiabilitiesAndAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tabular disclosure of discount rate and remaining lease term of operating and financial leases.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfDiscountRateAndLeaseTermUsedInCalculatingLeaseLiabilitiesAndAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Discount Rate And Lease Term Used In Calculating Lease Liabilities And Assets [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfDiscountRateAndLeaseTermUsedInCalculatingLeaseLiabilitiesAndAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Weighted Average Discount Rate and Lease Term Used in Calculating Lease Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Frequency [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Payments to Acquire Property, Plant, and Equipment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchases of property, plant and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfRestructuringDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Type of Restructuring [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OptionToPurchaseAdditionalDebtFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Option to purchase additional debt face amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OptionToPurchaseAdditionalDebtFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Option to Purchase Additional Debt Face Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OptionToPurchaseAdditionalDebtFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Additional Notes issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAndOtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAndOtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax and Other Liabilities, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncomeTaxReconciliationReturnToProvisionAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Income Tax Reconciliation Return to Provision Adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncomeTaxReconciliationReturnToProvisionAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Reconciliation Return to Provision Adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncomeTaxReconciliationReturnToProvisionAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Return to provision adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Shares, Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, New Issues</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Employee-related Liabilities, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee-related Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ArtesynBiosolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">ARTeSYN Biosolutions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ArtesynBiosolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">ARTeSYN Biosolutions [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ArtesynBiosolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ARTeSYN Biosolutions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ArtesynBiosolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">ARTeSYN</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business Acquisition [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Revenue, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Revenue, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_NorthAmericaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">North America [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_NorthAmericaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">North America</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveSecuritiesEffectOnBasicEarningsPerShareContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive securities effect on basic earnings per share contingent consideration.</link:label>
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  <xsd:element id="rgen_RevenueAndVolumeDiscountRate" name="RevenueAndVolumeDiscountRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="rgen_AcceleratedDepreciationMember" name="AcceleratedDepreciationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_MilliporeSigmaMember" name="MilliporeSigmaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_DebtInstrumentAccruedAndUnpaidInterest" name="DebtInstrumentAccruedAndUnpaidInterest" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_ProbabilityOfSuccess" name="ProbabilityOfSuccess" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="rgen_FacilityDomain" name="FacilityDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ScheduleOfDiscountRateAndLeaseTermUsedInCalculatingLeaseLiabilitiesAndAssetsTableTextBlock" name="ScheduleOfDiscountRateAndLeaseTermUsedInCalculatingLeaseLiabilitiesAndAssetsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_MeasurementInputRevenueVolumeDiscountRateMember" name="MeasurementInputRevenueVolumeDiscountRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ConvertibleNotesTransactionCostsOfLiabilityComponent" name="ConvertibleNotesTransactionCostsOfLiabilityComponent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_DeferredTaxAssetsOperatingLeases" name="DeferredTaxAssetsOperatingLeases" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_FairValueOfEmbeddedConversionOptionMember" name="FairValueOfEmbeddedConversionOptionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_CTechnologiesMember" name="CTechnologiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_NewtonNewJerseyMember" name="NewtonNewJerseyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_CommitmentsAndContingenciesTable" name="CommitmentsAndContingenciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_WeightedAverageDiscountRate" name="WeightedAverageDiscountRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="rgen_OtherProductsMember" name="OtherProductsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_NetWorkingCapitalExcludingCashAndInventory" name="NetWorkingCapitalExcludingCashAndInventory" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_DilutiveSharesEffectOnBasicEarningsPerShareAbstract" name="DilutiveSharesEffectOnBasicEarningsPerShareAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_DeferredIncomeTaxLiabilitiesFixedAssets" name="DeferredIncomeTaxLiabilitiesFixedAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_SpectrumIncMember" name="SpectrumIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_NumberOfSharesBasicOutstanding" name="NumberOfSharesBasicOutstanding" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_TrdArrExpirationDate" name="TrdArrExpirationDate" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_RevenueAndVolumeProjectionsPerformancePeriod" name="RevenueAndVolumeProjectionsPerformancePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedLiabilities" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_StockOptionAndIncentivePlanMember" name="StockOptionAndIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_SubscriptionTransactionMember" name="SubscriptionTransactionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_DeferredTaxLiablitiesMember" name="DeferredTaxLiablitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ExchangeTransactionMember" name="ExchangeTransactionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_FurnitureFixturesAndOfficeEquipmentMemberMember" name="FurnitureFixturesAndOfficeEquipmentMemberMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_MeasurementInputEarnoutDiscountRateMember" name="MeasurementInputEarnoutDiscountRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_IncomeTaxesLineItems" name="IncomeTaxesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseContingentConsiderationAmount" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseContingentConsiderationAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_FairValueOfSharesOfCommonStockIssuedForContingentConsiderationEarnouts" name="FairValueOfSharesOfCommonStockIssuedForContingentConsiderationEarnouts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_AvitideLlcMember" name="AvitideLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_CashConsiderationExcludingRestrictedCash" name="CashConsiderationExcludingRestrictedCash" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_FacilityAndOtherExitCostsMember" name="FacilityAndOtherExitCostsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_EffectiveIncomeTaxRateReconciliationForeignExchangeLossPercent" name="EffectiveIncomeTaxRateReconciliationForeignExchangeLossPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_CashCashEquivalentsAndMarketableSecuritiesHeldToMaturityTableTextBlock" name="CashCashEquivalentsAndMarketableSecuritiesHeldToMaturityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_TaxYearTwoThousandThirtySevenMember" name="TaxYearTwoThousandThirtySevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ScheduleOfDeferredTaxAssetsAndLiabilitiesTable" name="ScheduleOfDeferredTaxAssetsAndLiabilitiesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_UncategorizedAbstract" name="UncategorizedAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsNonvestedNumberOfShares" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsNonvestedNumberOfShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="rgen_ProbabilityWeightedPresentValueMember" name="ProbabilityWeightedPresentValueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssetNoncurrent" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssetNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_DilutiveSecuritiesEffectOnBasicEarningsPerShareContingentConsideration" name="DilutiveSecuritiesEffectOnBasicEarningsPerShareContingentConsideration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_NumberOfManufacturingSites" name="NumberOfManufacturingSites" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilityCurrent" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilityCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_ConvertibleNotesMember" name="ConvertibleNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_PercentageOfSharesSubjectToForfeiture" name="PercentageOfSharesSubjectToForfeiture" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="rgen_BusinessAcquisitionWorkingCapitalAdjustments" name="BusinessAcquisitionWorkingCapitalAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_ScheduleOfAmortizedCostAndFairValueDebtSecuritiesHeldToMaturityTableTextBlock" name="ScheduleOfAmortizedCostAndFairValueDebtSecuritiesHeldToMaturityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_PuroliteMember" name="PuroliteMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_BioflexAndNtmAcquisitionMember" name="BioflexAndNtmAcquisitionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_TwoZeroOneNineNotesMember" name="TwoZeroOneNineNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_DefinedContribution401KPlanMember" name="DefinedContribution401KPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_OutstandingTwoZeroTwoThreeNotesMember" name="OutstandingTwoZeroTwoThreeNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ZeroPointThreeSevenFivePercentConvertibleSeniorNotesDueTwentyTwentyFourMember" name="ZeroPointThreeSevenFivePercentConvertibleSeniorNotesDueTwentyTwentyFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_CashAndCashEquivalentsAndMoneyMarketFundsMember" name="CashAndCashEquivalentsAndMoneyMarketFundsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_IncomeTaxesTable" name="IncomeTaxesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_DilutiveSecuritiesEffectOnBasicEarningsPerShareConvertibleSeniorNotes" name="DilutiveSecuritiesEffectOnBasicEarningsPerShareConvertibleSeniorNotes" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_FederalAndStateMember" name="FederalAndStateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_RDAndCommercializationBasedPaymentsMember" name="RDAndCommercializationBasedPaymentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_SummaryOfSignificantAccountingPoliciesTable" name="SummaryOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ConvertibleNotesTransactionCostsOfEquityComponent" name="ConvertibleNotesTransactionCostsOfEquityComponent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_NoncashInterestIncome" name="NoncashInterestIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_AccruedLiabilitiesPolicyTextBlock" name="AccruedLiabilitiesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_ZeroPointThreeSevenFivePercentageConvertibleSeniorNotesDueTwentyTwentyFourMember" name="ZeroPointThreeSevenFivePercentageConvertibleSeniorNotesDueTwentyTwentyFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_VariableOperatingLeaseCost" name="VariableOperatingLeaseCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_EffectiveIncomeTaxRateReconciliationDebtDiscountPercentage" name="EffectiveIncomeTaxRateReconciliationDebtDiscountPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_NonExecutiveMember" name="NonExecutiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_DaylightSolutionsIncMember" name="DaylightSolutionsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_EffectiveIncomeTaxRateReconciliationForeignExchangeLoss" name="EffectiveIncomeTaxRateReconciliationForeignExchangeLoss" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_RgenFacilityDomain" name="RgenFacilityDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_EngineeredMoldingTechnologyLlcMember" name="EngineeredMoldingTechnologyLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_NGLImpactAMember" name="NGLImpactAMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_IncomeTaxRateReconciliationLineItems" name="IncomeTaxRateReconciliationLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ArtesynBiosolutionsHoldingsIrelandLimitedMember" name="ArtesynBiosolutionsHoldingsIrelandLimitedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_FlexbiosysIncMember" name="FlexbiosysIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ForeignEarningsSubjectToOneTimeTransitionTax" name="ForeignEarningsSubjectToOneTimeTransitionTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_LeaseObligationsNotYetCommenced" name="LeaseObligationsNotYetCommenced" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_LeaseIncentives" name="LeaseIncentives" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_InflationReductionActOfTwoThousandTwentyTwoMember" name="InflationReductionActOfTwoThousandTwentyTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilityNoncurrent" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilityNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_AvitideIncMember" name="AvitideIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_MonteCarloSimulationMember" name="MonteCarloSimulationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_StockIssuedDuringPeriodValueContingentConsiderationEarnoutPayment" name="StockIssuedDuringPeriodValueContingentConsiderationEarnoutPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_IndefiniteLivedIntangibleAssetsNet" name="IndefiniteLivedIntangibleAssetsNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_ProteinsProductsMember" name="ProteinsProductsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_RestrictedStockAndPerformanceStockUnitsMember" name="RestrictedStockAndPerformanceStockUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_EffectiveIncomeTaxRateReconciliationLossOnDebtExchangePercent" name="EffectiveIncomeTaxRateReconciliationLossOnDebtExchangePercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestNumber" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestNumber" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseContingentConsiderationPercent" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseContingentConsiderationPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_OnePointZeroZeroPercentConvertibleSeniorNotesDueTwentyTwentyEightMember" name="OnePointZeroZeroPercentConvertibleSeniorNotesDueTwentyTwentyEightMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ProcessAnalyticsProductsMember" name="ProcessAnalyticsProductsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ContingentConsiderationMember" name="ContingentConsiderationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_IncreaseDecreaseInOperatingLeaseLiabilities" name="IncreaseDecreaseInOperatingLeaseLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_StockholdersEquityNoteDisclosureTable" name="StockholdersEquityNoteDisclosureTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_AccumulatedDeficitMember" name="AccumulatedDeficitMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_RgenFacilityAxis" name="RgenFacilityAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_TaxYear2043Member" name="TaxYear2043Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ScheduleOfIncomeBeforeIncomeTaxLineItems" name="ScheduleOfIncomeBeforeIncomeTaxLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_LongTermContingentConsideration" name="LongTermContingentConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_CapacityOfBioreactors" name="CapacityOfBioreactors" type="dtr-types:volumeItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensation" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensation" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_OptionToPurchaseAdditionalDebtFaceAmount" name="OptionToPurchaseAdditionalDebtFaceAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_ScheduleOfAccruedLiabilitiesTable" name="ScheduleOfAccruedLiabilitiesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ScheduleOfIntangibleAssetsTable" name="ScheduleOfIntangibleAssetsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_SalesRevenuesGoodsNetMember" name="SalesRevenuesGoodsNetMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_OtherDirectorsOrOfficersMember" name="OtherDirectorsOrOfficersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_AdditionalUndiscountedInContingentConsiderationEarnoutPayments" name="AdditionalUndiscountedInContingentConsiderationEarnoutPayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_ScheduleOfBusinessCombinationConsiderationTransferredTableTextBlock" name="ScheduleOfBusinessCombinationConsiderationTransferredTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_IntangibleAssetsLineItems" name="IntangibleAssetsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_DilutiveEffectOnSharesOfConversionPremium" name="DilutiveEffectOnSharesOfConversionPremium" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_BioflexMember" name="BioflexMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_StockholdersEquityNoteDisclosureLineItems" name="StockholdersEquityNoteDisclosureLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_BusinessCombinationSeparatelyRecognizedTransactionsSettlementOfPreexistingInvoices" name="BusinessCombinationSeparatelyRecognizedTransactionsSettlementOfPreexistingInvoices" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_Rule10B51ArrModifiedFlag" name="Rule10B51ArrModifiedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_AvitideAndFlexbiosysMember" name="AvitideAndFlexbiosysMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_UnvestedOptionsMember" name="UnvestedOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_EarnoutConsiderationEarned" name="EarnoutConsiderationEarned" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="rgen_TwoZeroTwoThreeNotesMember" name="TwoZeroTwoThreeNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_PrepaidServicesAndProfessionalFees" name="PrepaidServicesAndProfessionalFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_ScheduleOfAccruedLiabilitiesLineItems" name="ScheduleOfAccruedLiabilitiesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_MetenovaHoldingAbMember" name="MetenovaHoldingAbMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ReconciliationOfBasicAndDilutedAbstract" name="ReconciliationOfBasicAndDilutedAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ContingentConsiderationExpense" name="ContingentConsiderationExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_DeferredTaxLiabilitiesDebtDiscount" name="DeferredTaxLiabilitiesDebtDiscount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_StockIssuedDuringPeriodSharesContingentConsiderationEarnoutPayments" name="StockIssuedDuringPeriodSharesContingentConsiderationEarnoutPayments" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_SummaryOfSignificantAccountingPoliciesLineItems" name="SummaryOfSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_IncomeTaxReconciliationNondeductibleExpenseExecutiveCompensation" name="IncomeTaxReconciliationNondeductibleExpenseExecutiveCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_NotesMember" name="NotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_RevenueAndVolumeBasedPaymentsMember" name="RevenueAndVolumeBasedPaymentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_DiscountRate" name="DiscountRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_IncreaseDecreaseInOperatingLeaseAsset" name="IncreaseDecreaseInOperatingLeaseAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_CommitmentsAndContingenciesLineItems" name="CommitmentsAndContingenciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ManufacturingLineExpansionsMember" name="ManufacturingLineExpansionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ModifiedTwoZeroOneNineNotesMember" name="ModifiedTwoZeroOneNineNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_DebtInstrumentIssuedForCash" name="DebtInstrumentIssuedForCash" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_NonEmployeeDirectorStockOptionMember" name="NonEmployeeDirectorStockOptionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ShortTermContingentConsideration" name="ShortTermContingentConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_ModificationOfDebt" name="ModificationOfDebt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_DebtInstrumentFaceAmountInCash" name="DebtInstrumentFaceAmountInCash" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_BusinessCombinationsCashDepositedInEscrowAccount" name="BusinessCombinationsCashDepositedInEscrowAccount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_ScheduleOfCashAndCashEquivalentsAndRestrictedCashTableTextBlock" name="ScheduleOfCashAndCashEquivalentsAndRestrictedCashTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_APACOtherMember" name="APACOtherMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_RisksAndUncertaintiesInEntitiesBusinessPolicyTextBlock" name="RisksAndUncertaintiesInEntitiesBusinessPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_DebtInstrumentExchangedAmount" name="DebtInstrumentExchangedAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_DefinedContributionPlanEmployeeEligibilityAge" name="DefinedContributionPlanEmployeeEligibilityAge" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_AbstractOfOperatingLeaseLiabilityFromBalanceSheetTableTextBlockTableTextBlock" name="AbstractOfOperatingLeaseLiabilityFromBalanceSheetTableTextBlockTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_AssetsNonCurrentExcludingDifferedTaxAssets" name="AssetsNonCurrentExcludingDifferedTaxAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_BusinessCombinationTransactionCostPaidDuringPeriod" name="BusinessCombinationTransactionCostPaidDuringPeriod" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_ComputerHardwareAndSoftwareMemberMember" name="ComputerHardwareAndSoftwareMemberMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_BusinessCombinationConsiderationIndemnificationEscrow" name="BusinessCombinationConsiderationIndemnificationEscrow" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_PfizerMember" name="PfizerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_AvailableForSaleSecuritiesEstimatedFairValue" name="AvailableForSaleSecuritiesEstimatedFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseAsset" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_UnlimitedCarryforwardPeriodMember" name="UnlimitedCarryforwardPeriodMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_InventoryAdjustmentsMember" name="InventoryAdjustmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_APACMember" name="APACMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_DebtSecuritiesHeldToMaturityAndCashAndCashEquivalentsEstimatedFairValue" name="DebtSecuritiesHeldToMaturityAndCashAndCashEquivalentsEstimatedFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_DeferredTaxLiabilitiesOperatingLeaseRightOfUseAssets" name="DeferredTaxLiabilitiesOperatingLeaseRightOfUseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_DebtSecuritiesHeldToMaturityAndCashAndCashEquivalentsAmortizedCosts" name="DebtSecuritiesHeldToMaturityAndCashAndCashEquivalentsAmortizedCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_ScheduleOfPropertyAndEquipmentUsefulLivesTableTextBlock" name="ScheduleOfPropertyAndEquipmentUsefulLivesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_DebtSecuritiesHeldToMaturityEstimatedFairValue" name="DebtSecuritiesHeldToMaturityEstimatedFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_PolymemSAMember" name="PolymemSAMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ScheduleOfIncomeBeforeIncomeTaxTable" name="ScheduleOfIncomeBeforeIncomeTaxTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_VolatilityRateOfContingentConsideration" name="VolatilityRateOfContingentConsideration" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="rgen_AcquisitionDateFairValueOfContingentConsiderationEarnouts" name="AcquisitionDateFairValueOfContingentConsiderationEarnouts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_TaxYear2040Member" name="TaxYear2040Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ScheduleOfSupplementalDisclosureOfCashFlowsRelatedToOperatingLeasesTableTextBlock" name="ScheduleOfSupplementalDisclosureOfCashFlowsRelatedToOperatingLeasesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_PercentageOfCurrentFederalTaxExpenseBenefit" name="PercentageOfCurrentFederalTaxExpenseBenefit" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_CustomerNumberOneMember" name="CustomerNumberOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_PrepaidExpensesAndOtherCurrentAssetsLineItems" name="PrepaidExpensesAndOtherCurrentAssetsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_WeightedAverageNumberOfSharesDilutiveEffectOfUnvestedPerformanceStockUnits" name="WeightedAverageNumberOfSharesDilutiveEffectOfUnvestedPerformanceStockUnits" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_DeferredTaxImpactOnConversionFeature" name="DeferredTaxImpactOnConversionFeature" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_ScheduleOfEarningsPerShareBasicAndDilutedLineItems" name="ScheduleOfEarningsPerShareBasicAndDilutedLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_CTechnologiesIncMember" name="CTechnologiesIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_DebtInstrumentConvertibleIntoEquity" name="DebtInstrumentConvertibleIntoEquity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_FiniteLivedIntangibleLiabilitiesLineItems" name="FiniteLivedIntangibleLiabilitiesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_CashAndMoneyMarketFundsMember" name="CashAndMoneyMarketFundsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_UnrecognizedTaxBenefitsPeriodGrossDecreasesRelease" name="UnrecognizedTaxBenefitsPeriodGrossDecreasesRelease" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_DebtInstrumentFaceAmountRemaining" name="DebtInstrumentFaceAmountRemaining" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_PrepaidExpensesAndOtherCurrentAssetsTable" name="PrepaidExpensesAndOtherCurrentAssetsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_AmortizationOfInventoryStepUp" name="AmortizationOfInventoryStepUp" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_EffectiveIncomeTaxRateReconciliationDebtDiscount" name="EffectiveIncomeTaxRateReconciliationDebtDiscount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_DebtSecuritiesMaturityWithinOneYearAmortizedCost" name="DebtSecuritiesMaturityWithinOneYearAmortizedCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_TrueUpCostsDecember2020Member" name="TrueUpCostsDecember2020Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ScheduleOfDeferredTaxAssetsAndLiabilitiesLineItems" name="ScheduleOfDeferredTaxAssetsAndLiabilitiesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_OptionToPurchaseCommonStockMember" name="OptionToPurchaseCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_MeasurementInputProbabilityOfSuccessMember" name="MeasurementInputProbabilityOfSuccessMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_FiltrationProductsMember" name="FiltrationProductsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilityNonCurrent" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilityNonCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_DebtInstrumentExchangedAmountCancelled" name="DebtInstrumentExchangedAmountCancelled" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_DebtInstrumentExchangeAmount" name="DebtInstrumentExchangeAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_IncomeTaxRateReconciliationTable" name="IncomeTaxRateReconciliationTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_TaxYear2041Member" name="TaxYear2041Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_FacilityExitAndOtherExitCostsMember" name="FacilityExitAndOtherExitCostsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ChromatographyProductsMember" name="ChromatographyProductsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_CoronavirusAidReliefAndEconomicSecurityFundValue" name="CoronavirusAidReliefAndEconomicSecurityFundValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_NoncashInventoryAdjustments" name="NoncashInventoryAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_ScheduleOfEarningsPerShareBasicAndDilutedTable" name="ScheduleOfEarningsPerShareBasicAndDilutedTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
</xsd:schema>
