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          <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="rgen_September2025Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">September 2025 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_September2025Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">September 2025 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_September2025Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">September 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Goodwill, Expected Tax Deductible, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill allocated deductible for income tax purposes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity [Abstract]</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="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="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/terseLabel">Metenova Holding AB</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_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level 2</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 2 [Member]</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_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="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="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_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</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_EarningsPerShareBasicAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Basic [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasicAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Denominator:</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_RestructuringAndRelatedCostCostIncurredToDate1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring and Related Cost, Cost Incurred to Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringAndRelatedCostCostIncurredToDate1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total pre-tax restructuring activity</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="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="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="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Shell Company</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_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_DebtInstrumentExchangedAmountCancelled_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Exchanged Amount Cancelled</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>
          <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 Equivalent</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/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/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/totalLabel">Cash and Cash Equivalents, at Carrying Value, Total</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_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="rgen_RDAndCommercializationBasedPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">R&amp;D and Commercialization-based payments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RDAndCommercializationBasedPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">R&amp;D and Commercialization-based Payments [Member]</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MeasurementInputEarnoutDiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Measurement Input Earnout Discount Rate.</link:label>
          <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_MeasurementInputEarnoutDiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout Discount Rate</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/terseLabel">Conversion of debt (in shares)</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_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>
          <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="rgen_SalesRevenuesGoodsNetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sales Revenues Goods Net.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SalesRevenuesGoodsNetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sales Revenues Goods Net [Member]</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Class [Domain]</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_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets acquired under operating leases</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/label">Right-of-Use Asset Obtained in Exchange for Operating Lease Liability</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/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_PaymentsToAcquireBusinessesGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Businesses, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross_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_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="us-gaap_BusinessAcquisitionAcquireeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAcquireeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business Acquisition, Acquiree [Domain]</link:label>
          <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>
          <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="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="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_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity</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/totalLabel">Total liabilities and stockholders' equity</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="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_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="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options exercisable at September 30, 2025</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="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_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</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/label">Restructuring and Related Costs [Table Text Block]</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDerivativeInstrumentsEffectOnOtherComprehensiveIncomeLossTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDerivativeInstrumentsEffectOnOtherComprehensiveIncomeLossTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Effects of Derivative Instruments on the Consolidated Statements of Comprehensive Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Line Items]</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="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/verboseLabel">Provisional goodwill</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/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/2009/role/negatedLabel">Other adjustments and non-cash items</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/terseLabel">Income tax (benefit) provision</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/verboseLabel">Effective 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/label">Effective Income Tax Rate Reconciliation, Percent</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">Effective Income Tax Rate Reconciliation, Percent, Total</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 Jurisdiction [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="us-gaap_ProceedsFromConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Convertible Debt</link:label>
          <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>
          <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="rgen_RestructuringReserveGainLossOnNonCashItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring Reserve, Gain (Loss) on Non Cash Items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RestructuringReserveGainLossOnNonCashItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of increase decrease in the reserve for full or partial settlement through consideration other than cash.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RestructuringReserveGainLossOnNonCashItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-cash Restructuring Items</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="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_IntercompanyForeignCurrencyBalanceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign notional amounts of the outstanding contracts balances</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntercompanyForeignCurrencyBalanceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intra-Entity Foreign Currency Balance, Amount</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_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination, recognized identifiable assets acquired and liabilities assumed, deferred tax liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Liability Assumed, Lease Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Operating lease liabilities</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/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/terseLabel">Additional paid-in capital</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/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/2009/role/negatedTerseLabel">Unamortized debt issuance costs</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="us-gaap_DeferredFinanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unamortized debt issuance costs</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="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="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="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_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/2003/role/terseLabel">Tax withholding on vesting of restricted stock units</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 units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockAmountConverted1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amount paid in cash for coversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockAmountConverted1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conversion of Stock, Amount Converted</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_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="rgen_OptionsToPurchaseCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options to Purchase Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OptionsToPurchaseCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Options to Purchase Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OptionsToPurchaseCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Options to purchase common stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Useful Life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetUsefulLife_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="us-gaap_FiniteLivedIntangibleAssetUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected useful life</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/terseLabel">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_VestingDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Vesting [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VestingDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vesting [Domain]</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="rgen_AmortizationOfDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">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/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/2009/role/negatedLabel">Amortization of debt issuance costs</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_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/terseLabel">Trademark and tradename</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="us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock_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>
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          <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_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Earnings Per Share, Basic, Total</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentExchangedAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt Instrument Exchanged Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentExchangedAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Exchanged Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtInstrumentExchangedAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument exchanged amount</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Foreign currency translation adjustment</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Options outstanding at December 31, 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Options outstanding at September 30, 2025</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/terseLabel">Fair value of common stock issued for acquisition</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_StockIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Fair value of 31,415 shares of common stock issued for the acquisition of FlexBiosys, Inc.</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="us-gaap_IncreaseDecreaseInAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accounts Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accounts receivable</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">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [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="us-gaap_HedgingDesignationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Hedging Designation [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_InventoryStep-UpAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory step-up amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_InventoryStep-UpAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory step-up amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_InventoryStep-UpAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Inventory step-up amortization.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share recalculated value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Exercise Price</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>
          <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_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_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 interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoThousandTwentyFourAwardAmendmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2024 Award Amendment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoThousandTwentyFourAwardAmendmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty Four Award Amendment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoThousandTwentyFourAwardAmendmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand twenty four award amendment.</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="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_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="srt_ConsolidationItemsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Consolidation Items [Domain]</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="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="us-gaap_ScheduleOfNotionalAmountsOfOutstandingDerivativePositionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfNotionalAmountsOfOutstandingDerivativePositionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Notional Amounts of the Outstanding Contracts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_HedgingDesignationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Hedging Designation [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accrued Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Accrued Liabilities, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accrued liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses</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/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/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">Retained earnings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeographicConcentrationRiskMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographic Concentration Risk [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeographicConcentrationRiskMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Geographic Concentration Risk [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value</link:label>
          <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>
          <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="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Flag</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="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="rgen_PerformanceBasedRestrictedStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Performance Based Restricted Stock Units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PerformanceBasedRestrictedStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Performance Based Restricted Stock Units[ Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PerformanceBasedRestrictedStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Performance based restricted stock units.</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/terseLabel">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_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">LIABILITIES AND STOCKHOLDERS' EQUITY</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="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation</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="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 liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPricePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Redemption Price, Percentage</link:label>
          <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_SegmentReportingCodmProfitLossMeasureHowUsedDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description</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_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Inventory, Current</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_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_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment</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/periodEndLabel">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Ending 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/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>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_FlexbiosysIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">FlexBiosys</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_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="us-gaap_AmortizationOfDebtDiscountPremium_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Debt Discount (Premium)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfDebtDiscountPremium_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of debt discount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfDebtDiscountPremium_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Amortization of debt discount and issuance costs</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 of the liability component</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiabilityMeasurementInput_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Liability, Measurement Input</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiabilityMeasurementInput_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business combination, contingent consideration, liability, measurement input</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_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_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_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/verboseLabel">(Loss) earnings per share:</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RestrictedStockAndOptionToPurchaseCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted Stock and Option to Purchase Common Stock</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RestrictedStockAndOptionToPurchaseCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restricted stock and option to purchase common stock.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Outstanding derivative instruments amounts</link:label>
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          <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="rgen_FacilityExitAndOtherExitCostsMember_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_May2025Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">May 2025 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_May2025Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">May 2025 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_May2025Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">May 2025</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized gain (loss) on available-for-sale securities, net of tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Unrealized gain (loss) on available-for-sale securities, net of tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ChiefCommercialOfficerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Chief Commercial Officer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ChiefCommercialOfficerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Chief Commercial Officer [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ChiefCommercialOfficerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Chief commercial officer.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ChiefFinancialOfficerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Chief Financial Officer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ChiefFinancialOfficerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Chief Financial Officer [Member]</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Land_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Land</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="rgen_ApacOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">APAC 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</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 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/terseLabel">APAC Other [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestOnConvertibleDebtNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest on Convertible Debt, Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestOnConvertibleDebtNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Charges associated with convertible debt instruments, net of tax</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_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/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_PerformanceStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Performance Stock Units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PerformanceStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Performance Stock Units [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_PerformanceStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Performance stock units.</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_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="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_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation</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 (decrease) increase in cash and cash equivalents</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="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="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="us-gaap_TypeOfAdoptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update [Domain]</link:label>
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          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease right of use asset amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfFinancialPositionLocationActivityAccrualAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position Location, Activity, Accrual [Axis]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Exercised</link:label>
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          <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_CostOfSalesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Sales [Member]</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>
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          <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>
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          <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>
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          <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="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_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Unvested at March 31, 2024</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, 2024</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 September 30,2025</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/label">Stock Issued During Period, Value, Conversion of Convertible Securities</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/terseLabel">Conversion of Convertible Securities Stock Issued | value</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_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/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/terseLabel">Preferred stock, shares outstanding</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_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_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="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="rgen_TanttiLaboratoryIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tantti Laboratory Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TanttiLaboratoryIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tantti Laboratory Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TanttiLaboratoryIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tantti Laboratory Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityRevenueRecognized_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_ContractWithCustomerLiabilityRevenueRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability, Revenue Recognized</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 Combination, Transaction Cost, Excluding Separately Recognized Transaction</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_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_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 units (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 units (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]</link:label>
          <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_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_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="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/terseLabel">Fair Value Of Embedded Conversion Option</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EarnoutOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout One [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EarnoutOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout one.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EarnoutOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout 1</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_DeferredIncomeTaxAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income Tax Assets, Net</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/totalLabel">Deferred Income Tax Assets, Net, Total</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/verboseLabel">Deferred tax assets</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="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Member]</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_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_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_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_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/verboseLabel">Other assets, long-term</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 Asset Acquired, Prepaid Expense and Other Asset, Current</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="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Award split, 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">Award split, 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/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_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basis of Presentation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Basis of Presentation and Significant Accounting Policies [Text Block]</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/verboseLabel">Equity award, grant date 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">Equity award, grant date 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/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_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue_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, Aggregate Intrinsic Value</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 expected to vest at September 30, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebt_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_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_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_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 Loss</link:label>
          <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>
          <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_CashMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash</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_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_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/totalLabel">Business Combination, Consideration Transferred, Total</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="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_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_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/2009/role/negatedLabel">Noncurrent operating lease liability</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="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/terseLabel">Preferred stock, $0.01 par value, 5,000,000 shares authorized, no shares issued or outstanding</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_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Finite-Lived</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/terseLabel">Fair Value</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 Asset Acquired, Identifiable Intangible Asset, Excluding 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">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/terseLabel">Fair value of acquired finite lived intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Selling, General and Administrative Expense</link:label>
          <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_SellingGeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Selling, General and Administrative Expense, Total</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="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="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted Average, Awarded</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than 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_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average grant date fair value of restricted stock units granted</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="rgen_NoOneCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">No One Customer [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NoOneCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">No one customer.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NoOneCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">No One Customer</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="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/terseLabel">Noncurrent deferred tax liability</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/terseLabel">Amortization expense</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_SegmentReportingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting [Abstract]</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 Asset Acquired, Asset</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="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Provisional fair value of net tangible assets acquired</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="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_BusinessCombinationsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business Combinations</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_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_ProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product</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">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_RestructuringAndRelatedActivitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring and Related Activities Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringAndRelatedActivitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restructuring Activities and Other Inventory-Related Charges</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transactions [Abstract]</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">Ending 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">Beginning Balance (in shares)</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/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/verboseLabel">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/terseLabel">Accounts receivable, net of reserves of $2,274 and $1,832 at September 30, 2025 and December 31, 2024, respectively</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="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and contingencies (Note 11)</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/verboseLabel">Commitments and contingencies (Note 14)</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="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Weighted Average, Unvested at December 31,2024</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 September 30,2025</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/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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture, Total</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_GoodwillPurchaseAccountingAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill, Measurement Period Adjustment</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillPurchaseAccountingAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Measurement period adjustments to provisional goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentConsiderationTransferred_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in preliminary purchase price allocation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentConsiderationTransferred_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScenarioForecastMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Scenario Forecast</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScenarioForecastMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Forecast [Member]</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_TwoThousandAndTwentyFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoThousandAndTwentyFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand and Twenty Four [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoThousandAndTwentyFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand and twenty four.</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="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="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/terseLabel">Unvested Options</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_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/terseLabel">Manufacturing Line Expansions</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_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation</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_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="us-gaap_ScheduleOfRestructuringReserveByTypeOfCostTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Charges Related to Restructuring Activities by Type of Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RealEstateHeldForDevelopmentAndSalePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Real Estate Held for Development and Sale, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RealEstateHeldForDevelopmentAndSalePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets Held for Sale</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 Asset Acquired, Cash and Cash Equivalent</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="us-gaap_AccruedIncomeTaxesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Income Taxes, Current</link:label>
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          <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="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/terseLabel">Probability Weighted Present Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_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_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Weighted Average Number of Shares Outstanding, Basic, Total</link:label>
          <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 (loss) per share - basic</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_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="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="srt_StatementScenarioAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Scenario [Axis]</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_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options exercisable at March 31</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPlanModificationIncrementalCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Plan Modification, Incremental Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPlanModificationIncrementalCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation expense related to the equity modification</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 Grant Date Fair Value</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_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table]</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfRelatedPartyTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule Of Related Party [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfRelatedPartyTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Related Party [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfRelatedPartyTable_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="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/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_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/verboseLabel">Fair value of 42,621 shares of common stock issued for the Avitide, Inc. contingent consideration earnout</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/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/terseLabel">Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Subsequent Events</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_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/verboseLabel">Convertible Senior Notes due 2028, net</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">Carrying amount - Convertible Senior Notes due 2028, net</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_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_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_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/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/verboseLabel">Stock-based compensation expense</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_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/verboseLabel">Contingent consideration</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">Contingent consideration</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_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_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_StockholdersEquity_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_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total stockholders' equity</link:label>
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          <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="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="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/terseLabel">Exchanged 2019 Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OlivierLoeillotMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Olivier Loeillot [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OlivierLoeillotMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Olivier Loeillot.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_OlivierLoeillotMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Olivier Loeillot</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="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Remainder of Fiscal Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2025 (remaining three months)</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/label">Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment</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/label">Acquired Finite-Lived Intangible Asset, Residual Value</link:label>
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          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="country_US_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">U.S Entity</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="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_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_ScheduleOfAccruedLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Accrued Liabilities [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accrued Liabilities</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_BusinessAcquisitionEffectiveDateOfAcquisition1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Effective Date of Acquisition</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/verboseLabel">Business combination date of acquistion</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative Instruments and Hedging Activities Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NonEmployeeDirectorStockOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non Employee Director Stock Option[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/terseLabel">Non-Employee Directors</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_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="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="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="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cost of product revenue</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 Product and Service 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/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/terseLabel">Cost of goods sold</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 September 30, 2025</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="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_RelatedPartyTransactionsByRelatedPartyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related and Nonrelated Parties [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="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="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_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxNonDeductibleAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill allocated deductible for income tax purposes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxNonDeductibleAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition Purchase Price Allocation Goodwill Expected Tax Non Deductible Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxNonDeductibleAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business acquisition purchase price allocation goodwill expected tax non deductible amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance at December 31, 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Business Combination, Contingent Consideration, Liability, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance at September 30, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiability_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_NineHundredAndEightDevicesPATPortfolioAcquisitionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nine Hundred And Eight Devices PAT Portfolio Acquisition [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NineHundredAndEightDevicesPATPortfolioAcquisitionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Nine hundred and eight devices PAT portfolio acquisition.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NineHundredAndEightDevicesPATPortfolioAcquisitionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">908 Devices PAT Portfolio Acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Reportable Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of reportable segments</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_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Security Exchange Name</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="srt_EuropeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Europe [Member]</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/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/verboseLabel">Indefinite-lived intangible asset</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/verboseLabel">Principal amount</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/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/totalLabel">Total property, plant and equipment</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 (loss) before income taxes</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="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock units vested</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 September 30, 2025</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="rgen_IncomeTaxesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Income Taxes [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncomeTaxesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Taxes [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_IncomeTaxesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ModifiedTwoZeroOneNineNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Modified Two Zero One Nine Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ModifiedTwoZeroOneNineNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Modified Two Zero One Nine Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ModifiedTwoZeroOneNineNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Modified 2019 Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerDurationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Duration [Domain]</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_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_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="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_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation</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="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Total</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_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="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_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current</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_TitleOfIndividualAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title and Position [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_TitleOfIndividualAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Title of Individual [Axis]</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="rgen_DevicesIncBioprocessingAnalyticsPortfolioMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">908 Devices Inc. Bioprocessing Analytics Portfolio [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DevicesIncBioprocessingAnalyticsPortfolioMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">908 Devices Inc. Bioprocessing Analytics Portfolio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DevicesIncBioprocessingAnalyticsPortfolioMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">908 devices inc. bioprocessing analytics portfolio.</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_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options exercisable at September 30, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Senior Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SubsequentToTheConversion_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Subsequent to the conversion.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SubsequentToTheConversion_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent to the Conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SubsequentToTheConversion_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent to conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Useful Life (in years)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock units member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Units [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock Units</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Restricted Stock Unit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock Units (RSUs) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RestrictedStockUnitsRSUMember</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="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 (loss) income:</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="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_GoodwillMeasurementPeriodAdjustmentResultOfWorkingCapitalPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill Measurement Period Adjustment Result Of Working Capital Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_GoodwillMeasurementPeriodAdjustmentResultOfWorkingCapitalPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Goodwill measurement period adjustment result of working capital payment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_GoodwillMeasurementPeriodAdjustmentResultOfWorkingCapitalPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Measurement period adjustment result of working capital payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NondesignatedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Not Designated as Hedging Instrument [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NondesignatedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Not Designated as Hedging Instrument</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Fair Value, off-Balance-Sheet Risks [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Fair Value of Outstanding Derivative Instruments Recorded in the Accompanying Consolidate Balance Sheet</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="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/terseLabel">1.00% Convertible Senior Notes due 2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeInstrumentsGainLossLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative Instruments, Gain (Loss) [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignExchangeForwardMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign Exchange Forward</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignExchangeForwardMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Exchange Forward [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureOfEntitysReportableSegmentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]</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_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_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_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Diluted</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Denominator for diluted earnings (loss) per share - adjusted weighted average shares used in computing earnings (loss) per share - diluted</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="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cover [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoThousandTwentyFourGrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2024 Grants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoThousandTwentyFourGrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty Four Grants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoThousandTwentyFourGrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand twenty four grants.</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="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_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_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Forfeited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period</link:label>
          <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_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Liability Assumed, Other Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther_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_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="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/verboseLabel">Total Revenue</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="srt_ScenarioUnspecifiedDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Scenario [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Operating Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Number of operating segments</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_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_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and administrative</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>
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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/documentation">Facility and other exit costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerDurationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Duration [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MachineryAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Machinery and Equipment, Gross</link:label>
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          <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, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]</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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amount of loss recognized on derivatives</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 portion of grants</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_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/2009/role/negatedLabel">Forfeited/expired/cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationContingentConsiderationLiabilityCurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Liability, Current [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationContingentConsiderationLiabilityCurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination, contingent consideration, liability, current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationContingentConsiderationLiabilityCurrentMember_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="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Liability Assumed, Accounts Payable, Current</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_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="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/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/terseLabel">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/totalLabel">Net Carrying Value 1</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_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="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_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Gain (Loss) on Extinguishment of Debt, Total</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/label">Gain (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="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_MeasurementInputRevenueVolumeDiscountRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue &amp; Volume Discount Rate</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_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_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="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/terseLabel">Weighted Average, Vested and expected to vest at September 30,2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfProductInformationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nature of Operation, Product Information, Concentration of Risk [Table]</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/totalLabel">Restructuring Charges, Total</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/label">Restructuring Charges</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>
          <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_ShortTermDebtTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-Term Debt, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Recent Accounting Guidance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative Instruments, Gain (Loss) [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationContingentConsiderationLiabilityNoncurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Liability, Noncurrent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationContingentConsiderationLiabilityNoncurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination, contingent consideration, liability, noncurrent.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_BusinessCombinationContingentConsiderationLiabilityNoncurrentMember_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="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="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/terseLabel">Dilutive effect on shares of conversion premium</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_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/terseLabel">Exchange Transaction</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_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Restricted stock units and options, vesting period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_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_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>
          <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_EmployeeSeveranceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Severance and 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/verboseLabel">Severance &amp; Employee-Related Costs</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_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Liability Assumed, Liability</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 tangible liabilities assumed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ConvertibleInstrumentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of accounting policy related to convertible instruments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ConvertibleInstrumentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Instrument [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ConvertibleInstrumentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Instruments</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="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/terseLabel">Modification of debt</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/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/periodEndLabel">Common Stock, Shares, Outstanding, Ending Balance</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/periodStartLabel">Common Stock, Shares, Outstanding, Beginning Balance</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>
          <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 liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Transition Report</link:label>
          <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_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_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_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_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestNumber_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 Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestNumber_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 Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares, Vested and expected to vest at September 30,2025</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_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Range of Outcomes, Maximum, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business combination contingent consideration, Maximum amount</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/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/2009/role/negatedLabel">Acquisitions, net of cash acquired</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="rgen_ScheduleOfConvertiableNoteInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of convertiable note interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ScheduleOfConvertiableNoteInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of convertible note interest expense</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_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/terseLabel">Issuance of common stock pursuant to 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/verboseLabel">Earnout payment - equity element</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnings (Loss) Per Share</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_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_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income</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 (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Net income (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveOptionsAndStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Dilutive Options and Stock Units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveOptionsAndStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive options and stock units.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveOptionsAndStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Options and Stock Units [Member]</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</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/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/2009/role/negatedLabel">Inventories</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="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="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/terseLabel">Exchange And Subscription Agreements</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 (Payment for) Other Financing Activity</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_IntangibleAssetsNetExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Assets, Net (Excluding Goodwill)</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/terseLabel">Intangible assets, net</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/verboseLabel">Net Carrying Value</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>
          <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_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/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/2009/role/negatedLabel">Prepaid expenses and other current assets</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/terseLabel">Prepaid expenses 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/negatedTerseLabel">Prepaid expenses and other assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCostsAndDiscounts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Debt Issuance Costs and Discounts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCostsAndDiscounts_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Amortization of Debt Issuance Costs and Discounts, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCostsAndDiscounts_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="rgen_WeightedAverageNumberOfSharesDilutiveEffectOfPerformanceStockUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Dilutive Effect of Performance Stock Units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_WeightedAverageNumberOfSharesDilutiveEffectOfPerformanceStockUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted average number of shares dilutive effect of performance stock units.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_WeightedAverageNumberOfSharesDilutiveEffectOfPerformanceStockUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Performance stock units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringAndRelatedActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring and Related Activities [Abstract]</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoZeroTwoNineteenNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two zero two nineteen notes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoZeroTwoNineteenNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Zero Two Nineteen Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoZeroTwoNineteenNotesMember_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="us-gaap_DebtConversionConvertedInstrumentSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Conversion, Converted Instrument, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt conversion, stock issued as premium</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="rgen_SwedishKronaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Swedish Krona</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SwedishKronaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Swedish krona [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SwedishKronaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Swedish krona [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">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [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_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_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_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Amount eligible for grant</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">Eligible for grant</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_InterestExpenseNonoperating_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseNonoperating_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseNonoperating_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Interest Expense, Nonoperating, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseNonoperating_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Nonoperating</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_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/terseLabel">Options and stock units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Noncurrent Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_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_IncreaseDecreaseInOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other noncurrent assets</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/terseLabel">Summary of Receivables and Deferred Revenue from Contracts with Customers</link:label>
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          <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>
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          <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>
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          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_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_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Stock Options Exercised</link:label>
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          <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_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_StockIssuedDuringPeriodValueAcquisitions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock pursuant to the acquisition</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="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="srt_NorthAmericaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">North America [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseAndRentalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Leases, Rent Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseAndRentalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Rental expense</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="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="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Liability Assumed, Deferred Revenue, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Deferred revenue</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_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">Earnout payment - cash element</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/negatedTerseLabel">Earnout payment - cash element</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="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="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_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_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_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_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/terseLabel">Assets, fair value</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_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="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">Revenues, percentage by country</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">Concentration Risk, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SummaryOfSignificantAccountingPoliciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary Of Significant Accounting Policies [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SummaryOfSignificantAccountingPoliciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary Of Significant Accounting Policies [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SummaryOfSignificantAccountingPoliciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary Of Significant Accounting Policies [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total cash used in investing activities</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_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table]</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">Conversion of debt</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_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_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative Instruments and Hedging Activities Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Derivative Instruments</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_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_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Money Market Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Money Market</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 and Nonrelated Parties [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="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_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="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="dei_LegalEntityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Legal Entity [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LegalEntityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Legal Entity [Axis]</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">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, 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_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Property, Plant and Equipment, Net</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="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Options outstanding at December 31, 2024</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 September 30, 2025</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_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_BusinessCombinationDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [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>
          <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_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_OtherOperatingIncomeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Operating Income (Expense) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherOperatingIncomeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other (expenses) income, net</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">Statement of Income Location, Balance [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="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_ScheduleOfFiniteLivedIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Asset, Finite-Lived [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="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_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="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_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from financing activities</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="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_SellingAndMarketingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Selling and Marketing Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingAndMarketingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Selling and Marketing Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingAndMarketingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sales and marketing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Components [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Components [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RestructuringInventoryRelatedCharges_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory-related charges</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RestructuringInventoryRelatedCharges_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring Inventory Related Charges</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_RestructuringInventoryRelatedCharges_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restructuring inventory related charges.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Other income, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other income, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income, net</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_FairValueByAssetClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Class [Axis]</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_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_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired and Liability Assumed [Table Text Block]</link:label>
          <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="us-gaap_BusinessAcquisitionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [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="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>
          <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="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="rgen_GoodwillAndOtherIntangibleAssetsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Goodwill And Other Intangible Assets Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_GoodwillAndOtherIntangibleAssetsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill And Other Intangible Assets Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_GoodwillAndOtherIntangibleAssetsDisclosureAbstract_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="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_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/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/totalLabel">Impairment of Intangible Assets (Excluding Goodwill), Total</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="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_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/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, 2020</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, 2024</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 September 30, 2025</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_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price</link:label>
          <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>
          <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_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_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/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/terseLabel">Common stock, $0.01 par value; 80,000,000 shares authorized; 56,283,321 shares at September 30, 2025 and 56,091,677 shares at December 31, 2024 issued and outstanding</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="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="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="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 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/terseLabel">Royalty and other revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AvitideLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Avitide</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_AvitideLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Avitide LLC [Member]</link:label>
          <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_ScheduleOfWeightedAverageNumberOfSharesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Weighted Average Number of Shares [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfWeightedAverageNumberOfSharesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic and Diluted Weighted Average Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EarnoutThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout Three [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EarnoutThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout three.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EarnoutThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout 3</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Amortization of debt 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_AmortizationOfFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Amortization of debt 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/terseLabel">Amortization of debt discount and issuance costs</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_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_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, shares authorized</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_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="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_RepaymentsOfConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Repayment of Convertible Senior Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Repayments of Convertible Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Repayment of convertible debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Repayment of convertible debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party Transaction [Line Items]</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_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_ScheduleOfBusinessAcquisitionsByAcquisitionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Table]</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="rgen_MetenovaAbMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Metenova AB</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MetenovaAbMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Metenova AB [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_MetenovaAbMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Metenova AB.</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="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_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_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="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Other income (expenses)</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/totalLabel">Other income, net</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 (expenses) income, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares issued for excess conversion premium</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conversion of Stock, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Abstract]</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/label">Finite-Lived Intangible Asset, Expected Amortization, Year Three</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">2028</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 (benefit) 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/totalLabel">Income Tax Expense (Benefit), 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/label">Income tax provision (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/verboseLabel">Income tax provision (benefit)</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_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/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/totalLabel">Contract with Customer, Receivable, after Allowance for Credit Loss, Total</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_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">Proceeds from issuance of common stock, net</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_ContingentConsiderationByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Type [Axis]</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="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_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_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_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="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_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_DebtInstrumentConvertibleTermsOfConversionFeature_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, terms of conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleTermsOfConversionFeature_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Terms of Conversion Feature</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/totalLabel">Numerator for diluted earnings (loss) per share - net income (loss) 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_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_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="srt_ConsolidationItemsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Consolidation Items [Axis]</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>
          <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_PaymentsForRestructuring_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Amounts Paid in 2025</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/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/2009/role/negatedLabel">Purchases of property, plant and equipment</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">Payment for (Proceeds from) Other Investing Activity</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_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period</link:label>
          <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="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/totalLabel">Total assets</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>
          <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_ScheduleOfRestructuringAndRelatedCostsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring Cost [Table]</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/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/verboseLabel">Deferred income taxes, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Selling, General and Administrative Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpensesMember_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="rgen_DebtConversionConvertedInstrumentAmountPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash paid on settlement upon debt conversion.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtConversionConvertedInstrumentAmountPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Conversion Converted Instrument Amount Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DebtConversionConvertedInstrumentAmountPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt conversion, cash paid for principal amount and interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TanttiMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tantti</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TanttiMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tantti [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TanttiMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tantti.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsNonvestedNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">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/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_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_BusinessCombinationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Abstract]</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/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/verboseLabel">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="us-gaap_DebtConversionOriginalDebtAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Conversion, Original Debt, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionOriginalDebtAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt conversion original debt amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Information about Reportable Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingSegmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Segments [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingSegmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating segments</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_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2030 and thereafter</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/label">Title and Position [Domain]</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="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="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/terseLabel">Earnout consideration earned</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">Increase in fair value of contingent consideration earnouts</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">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/2009/role/negatedLabel">Decrease in fair value of contingent consideration earnouts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForRent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments for Rent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForRent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Rental expense</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_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_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_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_BusinessAcquisitionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ReconciliationOfBasicAndDilutedSharesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reconciliation of Basic and Diluted Shares [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_ReconciliationOfBasicAndDilutedSharesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reconciliation Of Basic And Diluted Shares Abstract</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_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_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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingInformationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Information [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AwardDateAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Award Date [Axis]</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetAndLiabilityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Balances from contracts with customers only:</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="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/terseLabel">Restricted Stock Units and Performance Stock Units</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 Interest</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="us-gaap_DerivativeLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Derivative liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative Liability, Current</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/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/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_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 (loss) from operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AwardDateDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Award Date [Domain]</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="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/terseLabel">Retained Earnings</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">Business Combination, Contingent Consideration, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockIssuedDuringPeriodSharesContingentConsiderationEarnoutPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock pursuant to contingent consideration earnout payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_StockIssuedDuringPeriodSharesContingentConsiderationEarnoutPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares,Contingent Consideration Earnout Payments</link:label>
          <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_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_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_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_ShareBasedCompensation_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_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/label">Share-Based Payment Arrangement, Noncash Expense</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_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="rgen_EarnoutTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout Two [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EarnoutTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout two.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_EarnoutTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout 2</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="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="rgen_NineHundredAndEightDevicesPATPortfolioMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nine Hundred And Eight Devices PAT Portfolio [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NineHundredAndEightDevicesPATPortfolioMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Nine hundred and eight devices PAT portfolio.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NineHundredAndEightDevicesPATPortfolioMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">908 Devices PAT Portfolio</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/label">Operating Lease, Liability, Noncurrent</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/verboseLabel">Noncurrent operating lease liabilities</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="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_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_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation</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 used in financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NoncashinventorywriteOff_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-cash inventory write-off</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NoncashinventorywriteOff_lbl" xlink:role="http://www.xbrl.org/2003/role/label">NoncashInventoryWrite-off</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NoncashinventorywriteOff_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">NoncashInventoryWrite-off.</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/terseLabel">Technology - developed</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</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/verboseLabel">Developed technology</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="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_ScheduleOfGoodwillTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">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_Rule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Rule 10b5 1 Arr Modified Flag</link:label>
          <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_Rule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Rule 10b5-1 Arrangement Modified</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 Asset Acquired, Receivable, Current</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_IncomeTaxAuthorityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Jurisdiction [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="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_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Income Location, Balance [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_OtherIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income (expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Income [Member]</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">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [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 for operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewDateOfAnnualGoodwillImpairmentTest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Date of Annual Goodwill Impairment Test</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/verboseLabel">Long-term 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">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/label">Increase (Decrease) in Other Noncurrent Liabilities</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>
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          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_DilutiveSecuritiesEffectOnBasicEarningsPerShareContingentConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Securities Effect On Basic Earnings Per Share Contingent Consideration</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_TwoZeroTwoThreeNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two zero two three Notes.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityEmergingGrowthCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Emerging Growth Company</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="rgen_NonExecutiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-Executive [Member]</link:label>
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          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:to="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_lbl"/>
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  <xsd:element id="rgen_SummaryOfSignificantAccountingPoliciesTable" name="SummaryOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_RestructuringReserveGainLossOnNonCashItems" name="RestructuringReserveGainLossOnNonCashItems" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_EarnoutThreeMember" name="EarnoutThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_RestructuringInventoryRelatedCharges" name="RestructuringInventoryRelatedCharges" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_DilutiveSharesEffectOnBasicEarningsPerShareAbstract" name="DilutiveSharesEffectOnBasicEarningsPerShareAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_TanttiMember" name="TanttiMember" 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_StockUnitsMember" name="StockUnitsMember" type="dtr-types:domainItemType" 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_BusinessCombinationContingentConsiderationLiabilityNoncurrentMember" name="BusinessCombinationContingentConsiderationLiabilityNoncurrentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_PerformanceBasedRestrictedStockUnitsMember" name="PerformanceBasedRestrictedStockUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ConvertibleInstrumentPolicyTextBlock" name="ConvertibleInstrumentPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsNonvestedNumberOfShares" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsNonvestedNumberOfShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <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_SalesRevenuesGoodsNetMember" name="SalesRevenuesGoodsNetMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_NoncashinventorywriteOff" name="NoncashinventorywriteOff" 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_ModificationOfDebt" name="ModificationOfDebt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTableTextBlock" name="ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_NineHundredAndEightDevicesPATPortfolioAcquisitionMember" name="NineHundredAndEightDevicesPATPortfolioAcquisitionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_GoodwillAndOtherIntangibleAssetsDisclosureAbstract" name="GoodwillAndOtherIntangibleAssetsDisclosureAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_TanttiLaboratoryIncMember" name="TanttiLaboratoryIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_PercentageOfSharesSubjectToForfeiture" name="PercentageOfSharesSubjectToForfeiture" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="rgen_TwoThousandTwentyFourGrantsMember" name="TwoThousandTwentyFourGrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_BusinessCombinationContingentConsiderationLiabilityCurrentMember" name="BusinessCombinationContingentConsiderationLiabilityCurrentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_SubscriptionTransactionsMember" name="SubscriptionTransactionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" 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_DebtInstrumentExchangedAmount" name="DebtInstrumentExchangedAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_FairValueOfSharesOfCommonStockIssuedForContingentConsiderationEarnouts" name="FairValueOfSharesOfCommonStockIssuedForContingentConsiderationEarnouts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_ScheduleOfEarningsPerShareBasicAndDilutedLineItems" name="ScheduleOfEarningsPerShareBasicAndDilutedLineItems" type="xbrli:stringItemType" 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_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilityNoncurrent" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilityNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestNumber" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestNumber" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_SubsequentToTheConversion" name="SubsequentToTheConversion" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_AmortizationOfDebtIssuanceCost" name="AmortizationOfDebtIssuanceCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_TwoThousandTwentyFourAwardAmendmentMember" name="TwoThousandTwentyFourAwardAmendmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_NoOneCustomerMember" name="NoOneCustomerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_WeightedAverageNumberOfSharesDilutiveEffectOfPerformanceStockUnits" name="WeightedAverageNumberOfSharesDilutiveEffectOfPerformanceStockUnits" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_ChiefCommercialOfficerMember" name="ChiefCommercialOfficerMember" 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_TwoThousandAndTwentyFourMember" name="TwoThousandAndTwentyFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_InventoryStep-UpAmortization" name="InventoryStep-UpAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rgen_EarnoutTwoMember" name="EarnoutTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_FiniteLivedIntangibleLiabilitiesLineItems" name="FiniteLivedIntangibleLiabilitiesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_IntangibleAssetsLineItems" name="IntangibleAssetsLineItems" 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_CashCashEquivalentsAndMarketableSecuritiesHeldToMaturityTableTextBlock" name="CashCashEquivalentsAndMarketableSecuritiesHeldToMaturityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" 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_AcceleratedDepreciationMember" name="AcceleratedDepreciationMember" 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_StockholdersEquityNoteDisclosureLineItems" name="StockholdersEquityNoteDisclosureLineItems" type="xbrli:stringItemType" 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_TwoZeroTwoNineteenNotesMember" name="TwoZeroTwoNineteenNotesMember" 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_NineHundredAndEightDevicesPATPortfolioMember" name="NineHundredAndEightDevicesPATPortfolioMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_ScheduleOfAccruedLiabilitiesTable" name="ScheduleOfAccruedLiabilitiesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_OptionToPurchaseAdditionalDebtFaceAmount" name="OptionToPurchaseAdditionalDebtFaceAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_EarnoutOneMember" name="EarnoutOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_MeasurementInputEarnoutDiscountRateMember" name="MeasurementInputEarnoutDiscountRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ExchangeAndSubscriptionAgreementsMember" name="ExchangeAndSubscriptionAgreementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ScheduleOfConvertiableNoteInterestExpense" name="ScheduleOfConvertiableNoteInterestExpense" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_DebtConversionConvertedInstrumentAmountPaid" name="DebtConversionConvertedInstrumentAmountPaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_GoodwillMeasurementPeriodAdjustmentResultOfWorkingCapitalPayment" name="GoodwillMeasurementPeriodAdjustmentResultOfWorkingCapitalPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rgen_September2025Member" name="September2025Member" 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_Rule10B51ArrModifiedFlag" name="Rule10B51ArrModifiedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rgen_ExchangedTwoZeroOneNineNotesMember" name="ExchangedTwoZeroOneNineNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rgen_ScheduleOfAccruedLiabilitiesLineItems" name="ScheduleOfAccruedLiabilitiesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
</xsd:schema>
