v2.4.1.9

Long-Term Debt Revolving Loan (Details) (USD $) | 12 Months Ended | 3 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2014 | Sep. 30, 2014 | Jul. 31, 2013
Debt Instrument [Line Items] |  |  |  |  |  |
Debt, long-term and short-term | $ 3,192,400,000 us-gaap_DebtInstrumentCarryingAmount |  |  | $ 3,192,400,000 us-gaap_DebtInstrumentCarryingAmount |  |
Gains (Losses) on Extinguishment of Debt | 90,700,000 us-gaap_GainsLossesOnExtinguishmentOfDebt | 64,000,000 us-gaap_GainsLossesOnExtinguishmentOfDebt | 17,200,000 us-gaap_GainsLossesOnExtinguishmentOfDebt |  |  |
Deferred Finance Costs, Noncurrent, Net | 33,000,000 us-gaap_DeferredFinanceCostsNoncurrentNet | 30,100,000 us-gaap_DeferredFinanceCostsNoncurrentNet | 53,200,000 us-gaap_DeferredFinanceCostsNoncurrentNet | 33,000,000 us-gaap_DeferredFinanceCostsNoncurrentNet |  |
Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt, long-term and short-term | 0 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember | 0 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  | 0 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Letters of Credit Outstanding, Amount | 2,100,000 us-gaap_LettersOfCreditOutstandingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 2,100,000 us-gaap_LettersOfCreditOutstandingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Floorplan sub-facility, reserve | 312,300,000 cdw_FloorplanSubFacilityReserve / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 312,300,000 cdw_FloorplanSubFacilityReserve / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Line of Credit Facility, Maximum Borrowing Capacity | 1,250,000,000.0 us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 1,250,000,000.0 us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Line of Credit Facility, Fee on Unused Portion, Basis Points | 25 cdw_LineOfCreditFacilityFeeOnUnusedPortionBasisPoints / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 25 cdw_LineOfCreditFacilityFeeOnUnusedPortionBasisPoints / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Line of Credit Facility, Decrease in Applicable Interest Rate Margin, Basis Points |  |  |  |  | 50 cdw_LineofCreditFacilityDecreaseinApplicableInterestRateMarginBasisPoints / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |
Gains (Losses) on Extinguishment of Debt | 400,000 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  |  |  |
Deferred Finance Costs, Noncurrent, Net | 6,400,000 us-gaap_DeferredFinanceCostsNoncurrentNet / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 6,400,000 us-gaap_DeferredFinanceCostsNoncurrentNet / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Variable Interest Rate Margin, ABR Determination, Basis Point Plus Federal Funds Effective Rate | 50 cdw_VariableInterestRateAbrDeterminationBasisPointPlusFederalFundsEffectiveRate / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 50 cdw_VariableInterestRateAbrDeterminationBasisPointPlusFederalFundsEffectiveRate / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Variable Interest Rate Margin, ABR Determination, Percentage Plus LIBOR | 1.00%cdw_VariableInterestRateAbrDeterminationPercentagePlusOneMonthLibor / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 1.00%cdw_VariableInterestRateAbrDeterminationPercentagePlusOneMonthLibor / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Potential Margin Reduction | 0.25%cdw_PotentialMarginReduction / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 0.25%cdw_PotentialMarginReduction / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Line of Credit Facility, Borrowing Base | 1,253,400,000 cdw_LineOfCreditFacilityBorrowingBase / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 1,253,400,000 cdw_LineOfCreditFacilityBorrowingBase / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Line of Credit Facility, Remaining Borrowing Capacity | 935,600,000 us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 935,600,000 us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Revolving Loan, Consecutive Business Days Below Minimum Average Daily Excess Cash Availability Requirement | 5 days |  |  |  |  |
Revolving Loan, Minimum Average Daily Excess Cash Availability Requirement, Consecutive Business Days Met | 30 days |  |  |  |  |
Line Of Credit Facility, Maximum Aggregate Increase | 300,000,000 cdw_LineOfCreditFacilityMaximumAggregateIncrease / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 300,000,000 cdw_LineOfCreditFacilityMaximumAggregateIncrease / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Revolving Loan Maturity Acceleration Provision, Days Prior to Maturity |  |  |  | 45 days |  |
Revolving Loan Maturity Acceleration Provision, Excess Cash Availability Limit, Amount Plus Maturing Debt | 150,000,000 cdw_RevolvingLoanMaturityAccelerationProvisionExcessCashAvailabilityLimitAmountPlusMaturingDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 150,000,000 cdw_RevolvingLoanMaturityAccelerationProvisionExcessCashAvailabilityLimitAmountPlusMaturingDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Minimum Liquidity Condition, Cash Availability | 125,000,000 cdw_MinimumLiquidityConditionCashAvailability / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 125,000,000 cdw_MinimumLiquidityConditionCashAvailability / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Cash Availability, Percentage of Borrowing Base | 10.00%cdw_CashAvailabilityPercentageofBorrowingBase / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 10.00%cdw_CashAvailabilityPercentageofBorrowingBase / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Minimum Liquidity Condition, Amount | 100,000,000 cdw_MinimumLiquidityConditionAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 100,000,000 cdw_MinimumLiquidityConditionAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Fixed Charge Coverage Ratio | 1.00 cdw_FixedChargeCoverageRatio / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 1.00 cdw_FixedChargeCoverageRatio / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Previous Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | 900,000,000 us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_LongtermDebtTypeAxis = cdw_PreviousRevolvingCreditFacilityMember |  |  | 900,000,000 us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_LongtermDebtTypeAxis = cdw_PreviousRevolvingCreditFacilityMember |  |
Line Of Credit Facility, Maximum Aggregate Increase | 200,000,000 cdw_LineOfCreditFacilityMaximumAggregateIncrease / us-gaap_LongtermDebtTypeAxis = cdw_PreviousRevolvingCreditFacilityMember |  |  | 200,000,000 cdw_LineOfCreditFacilityMaximumAggregateIncrease / us-gaap_LongtermDebtTypeAxis = cdw_PreviousRevolvingCreditFacilityMember |  |
Term Loan [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt, long-term and short-term | 1,513,500,000 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = cdw_TermLoanMember | 1,528,900,000 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = cdw_TermLoanMember |  | 1,513,500,000 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = cdw_TermLoanMember |  |
Gains (Losses) on Extinguishment of Debt |  | 10,300,000 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_LongtermDebtTypeAxis = cdw_TermLoanMember |  |  |  |
Deferred Finance Costs, Net |  |  |  |  |  | 6,100,000 us-gaap_DeferredFinanceCostsNet / us-gaap_LongtermDebtTypeAxis = cdw_TermLoanMember
Higher Utilization [Member] | Previous Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of Credit Facility, Fee on Unused Portion, Basis Points | 37.5 cdw_LineOfCreditFacilityFeeOnUnusedPortionBasisPoints / cdw_AverageDailyRevolvingCommitmentUtilizationAxis = cdw_HigherUtilizationMember / us-gaap_LongtermDebtTypeAxis = cdw_PreviousRevolvingCreditFacilityMember |  |  | 37.5 cdw_LineOfCreditFacilityFeeOnUnusedPortionBasisPoints / cdw_AverageDailyRevolvingCommitmentUtilizationAxis = cdw_HigherUtilizationMember / us-gaap_LongtermDebtTypeAxis = cdw_PreviousRevolvingCreditFacilityMember |  |
Lower Utilization [Member] | Previous Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of Credit Facility, Fee on Unused Portion, Basis Points | 50 cdw_LineOfCreditFacilityFeeOnUnusedPortionBasisPoints / cdw_AverageDailyRevolvingCommitmentUtilizationAxis = cdw_LowerUtilizationMember / us-gaap_LongtermDebtTypeAxis = cdw_PreviousRevolvingCreditFacilityMember |  |  | 50 cdw_LineOfCreditFacilityFeeOnUnusedPortionBasisPoints / cdw_AverageDailyRevolvingCommitmentUtilizationAxis = cdw_LowerUtilizationMember / us-gaap_LongtermDebtTypeAxis = cdw_PreviousRevolvingCreditFacilityMember |  |
LIBOR [Member] | Minimum [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Variable Interest Rate Margin | 1.50%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_LiborMember / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MinimumMember |  |  | 1.50%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_LiborMember / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MinimumMember |  |
LIBOR [Member] | Minimum [Member] | Term Loan [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Variable Interest Rate Margin | 2.25%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_LiborMember / us-gaap_LongtermDebtTypeAxis = cdw_TermLoanMember / us-gaap_RangeAxis = us-gaap_MinimumMember |  |  | 2.25%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_LiborMember / us-gaap_LongtermDebtTypeAxis = cdw_TermLoanMember / us-gaap_RangeAxis = us-gaap_MinimumMember |  |
LIBOR [Member] | Maximum [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Variable Interest Rate Margin | 2.00%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_LiborMember / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MaximumMember |  |  | 2.00%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_LiborMember / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MaximumMember |  |
LIBOR [Member] | Maximum [Member] | Term Loan [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Variable Interest Rate Margin | 2.50%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_LiborMember / us-gaap_LongtermDebtTypeAxis = cdw_TermLoanMember / us-gaap_RangeAxis = us-gaap_MaximumMember |  |  | 2.50%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_LiborMember / us-gaap_LongtermDebtTypeAxis = cdw_TermLoanMember / us-gaap_RangeAxis = us-gaap_MaximumMember |  |
ABR [Member] | Minimum [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Variable Interest Rate Margin | 0.50%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_AbrMember / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MinimumMember |  |  | 0.50%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_AbrMember / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MinimumMember |  |
ABR [Member] | Minimum [Member] | Term Loan [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Variable Interest Rate Margin | 1.25%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_AbrMember / us-gaap_LongtermDebtTypeAxis = cdw_TermLoanMember / us-gaap_RangeAxis = us-gaap_MinimumMember |  |  | 1.25%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_AbrMember / us-gaap_LongtermDebtTypeAxis = cdw_TermLoanMember / us-gaap_RangeAxis = us-gaap_MinimumMember |  |
ABR [Member] | Maximum [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Variable Interest Rate Margin | 1.00%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_AbrMember / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MaximumMember |  |  | 1.00%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_AbrMember / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MaximumMember |  |
ABR [Member] | Maximum [Member] | Term Loan [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Variable Interest Rate Margin | 1.50%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_AbrMember / us-gaap_LongtermDebtTypeAxis = cdw_TermLoanMember / us-gaap_RangeAxis = us-gaap_MaximumMember |  |  | 1.50%cdw_VariableInterestRateMargin / cdw_InterestRateBasisAxis = cdw_AbrMember / us-gaap_LongtermDebtTypeAxis = cdw_TermLoanMember / us-gaap_RangeAxis = us-gaap_MaximumMember |  |
Accounts Payable, Inventory Financing [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Revolving Loan financing agreement | 330,100,000 cdw_RevolvingLoanFinancingAgreement / cdw_InventoryFinancingAgreementsAxis = cdw_AccountsPayableInventoryFinancingMember | 256,100,000 cdw_RevolvingLoanFinancingAgreement / cdw_InventoryFinancingAgreementsAxis = cdw_AccountsPayableInventoryFinancingMember |  | 330,100,000 cdw_RevolvingLoanFinancingAgreement / cdw_InventoryFinancingAgreementsAxis = cdw_AccountsPayableInventoryFinancingMember |  |
Accounts Payable, Inventory Financing [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount owed under Revolving loan financing agreement | 312,300,000 cdw_AmountOwedUnderRevolvingLoanFinancingAgreement / cdw_InventoryFinancingAgreementsAxis = cdw_AccountsPayableInventoryFinancingMember / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 312,300,000 cdw_AmountOwedUnderRevolvingLoanFinancingAgreement / cdw_InventoryFinancingAgreementsAxis = cdw_AccountsPayableInventoryFinancingMember / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Floorplan sub-facility, variation in balance due to timing | 17,800,000 cdw_FloorplanSubFacilityVariationBetweenBalanceInFinancialsAndBalancePerFinancialIntermediaryDueToTimingDifferencesInReporting / cdw_InventoryFinancingAgreementsAxis = cdw_AccountsPayableInventoryFinancingMember / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |  | 17,800,000 cdw_FloorplanSubFacilityVariationBetweenBalanceInFinancialsAndBalancePerFinancialIntermediaryDueToTimingDifferencesInReporting / cdw_InventoryFinancingAgreementsAxis = cdw_AccountsPayableInventoryFinancingMember / us-gaap_LongtermDebtTypeAxis = us-gaap_RevolvingCreditFacilityMember |  |
Accounts Payable, Inventory Financing [Member] | Previous Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Floorplan sub-facility | $ 400,000,000 cdw_FloorplanSubFacility / cdw_InventoryFinancingAgreementsAxis = cdw_AccountsPayableInventoryFinancingMember / us-gaap_LongtermDebtTypeAxis = cdw_PreviousRevolvingCreditFacilityMember |  |  | $ 400,000,000 cdw_FloorplanSubFacility / cdw_InventoryFinancingAgreementsAxis = cdw_AccountsPayableInventoryFinancingMember / us-gaap_LongtermDebtTypeAxis = cdw_PreviousRevolvingCreditFacilityMember |  |
Percentage reserve for open orders under financing agreement |  |  |  |  | 15.00%cdw_PercentageReserveForOpenOrdersUnderFinancingAgreement / cdw_InventoryFinancingAgreementsAxis = cdw_AccountsPayableInventoryFinancingMember / us-gaap_LongtermDebtTypeAxis = cdw_PreviousRevolvingCreditFacilityMember |

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- Definition Amount owed under Revolving loan financing agreement + References No definition available. + Details
Name: | cdw_AmountOwedUnderRevolvingLoanFinancingAgreement
Namespace Prefix: | cdw_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Cash Availability, Percentage of Borrowing Base + References No definition available. + Details
Name: | cdw_CashAvailabilityPercentageofBorrowingBase
Namespace Prefix: | cdw_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fixed Charge Coverage Ratio + References No definition available. + Details
Name: | cdw_FixedChargeCoverageRatio
Namespace Prefix: | cdw_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | instant

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- Definition Floorplan sub-facility + References No definition available. + Details
Name: | cdw_FloorplanSubFacility
Namespace Prefix: | cdw_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Floorplan sub-facility, reserve + References No definition available. + Details
Name: | cdw_FloorplanSubFacilityReserve
Namespace Prefix: | cdw_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Floorplan sub-facility, variation between balance in financials and balance per financial intermediary due to timing differences in reporting + References No definition available. + Details
Name: | cdw_FloorplanSubFacilityVariationBetweenBalanceInFinancialsAndBalancePerFinancialIntermediaryDueToTimingDifferencesInReporting
Namespace Prefix: | cdw_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Line of Credit Facility, Borrowing Base + References No definition available. + Details
Name: | cdw_LineOfCreditFacilityBorrowingBase
Namespace Prefix: | cdw_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Line of Credit Facility, Decrease in Applicable Interest Rate Margin, Basis Points + References No definition available. + Details
Name: | cdw_LineofCreditFacilityDecreaseinApplicableInterestRateMarginBasisPoints
Namespace Prefix: | cdw_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

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- Definition Line of Credit Facility, Fee on Unused Portion, Basis Points + References No definition available. + Details
Name: | cdw_LineOfCreditFacilityFeeOnUnusedPortionBasisPoints
Namespace Prefix: | cdw_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line Of Credit Facility, Maximum Aggregate Increase + References No definition available. + Details
Name: | cdw_LineOfCreditFacilityMaximumAggregateIncrease
Namespace Prefix: | cdw_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Minimum Liquidity Condition, Amount + References No definition available. + Details
Name: | cdw_MinimumLiquidityConditionAmount
Namespace Prefix: | cdw_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition Minimum Liquidity Condition, Cash Availability + References No definition available. + Details
Name: | cdw_MinimumLiquidityConditionCashAvailability
Namespace Prefix: | cdw_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition Percentage reserve for open orders under financing agreement + References No definition available. + Details
Name: | cdw_PercentageReserveForOpenOrdersUnderFinancingAgreement
Namespace Prefix: | cdw_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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- Definition Potential Margin Reduction + References No definition available. + Details
Name: | cdw_PotentialMarginReduction
Namespace Prefix: | cdw_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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- Definition Revolving Loan, Consecutive Business Days Below Minimum Average Daily Excess Cash Availability Requirement + References No definition available. + Details
Name: | cdw_RevolvingLoanConsecutiveBusinessDaysBelowMinimumAverageDailyExcessCashAvailabilityRequirement
Namespace Prefix: | cdw_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Revolving Loan financing agreement + References No definition available. + Details
Name: | cdw_RevolvingLoanFinancingAgreement
Namespace Prefix: | cdw_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Revolving Loan Maturity Acceleration Provision, Days Prior to Maturity + References No definition available. + Details
Name: | cdw_RevolvingLoanMaturityAccelerationProvisionDaysPriorToMaturity
Namespace Prefix: | cdw_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Revolving Loan Maturity Acceleration Provision, Excess Cash Availability Limit, Amount Plus Maturing Debt + References No definition available. + Details
Name: | cdw_RevolvingLoanMaturityAccelerationProvisionExcessCashAvailabilityLimitAmountPlusMaturingDebt
Namespace Prefix: | cdw_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Revolving Loan, Minimum Average Daily Excess Cash Availability Requirement, Consecutive Business Days Met + References No definition available. + Details
Name: | cdw_RevolvingLoanMinimumAverageDailyExcessCashAvailabilityRequirementConsecutiveBusinessDaysMet
Namespace Prefix: | cdw_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Variable Interest Rate, ABR Determination, Basis Point Plus Federal Funds Effective Rate + References No definition available. + Details
Name: | cdw_VariableInterestRateAbrDeterminationBasisPointPlusFederalFundsEffectiveRate
Namespace Prefix: | cdw_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

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- Definition Variable Interest Rate, ABR Determination, Percentage Plus One-Month LIBOR + References No definition available. + Details
Name: | cdw_VariableInterestRateAbrDeterminationPercentagePlusOneMonthLibor
Namespace Prefix: | cdw_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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- Definition Variable Interest Rate Margin + References No definition available. + Details
Name: | cdw_VariableInterestRateMargin
Namespace Prefix: | cdw_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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- Definition Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 + Details
Name: | us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Details
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- Definition For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28555-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 17 -Article 5 + Details
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- Definition Net amount of long-term deferred finance costs capitalized at the end of the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28555-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 17 -Article 5 + Details
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- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12317-112629 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12355-112629 + Details
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- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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