v2.4.1.9

Long-Term Debt Senior Secured Notes (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Aug. 05, 2014 | Jul. 02, 2013
Debt Instrument [Line Items] |  |  |  |  |
Debt, long-term and short-term | $ 3,192.4 us-gaap_DebtInstrumentCarryingAmount |  |  |  |
Gains (Losses) on Extinguishment of Debt | 90.7 us-gaap_GainsLossesOnExtinguishmentOfDebt | 64.0 us-gaap_GainsLossesOnExtinguishmentOfDebt | 17.2 us-gaap_GainsLossesOnExtinguishmentOfDebt |  |
Write off of Deferred Debt Issuance Cost | 12.6 us-gaap_WriteOffOfDeferredDebtIssuanceCost | 20.1 us-gaap_WriteOffOfDeferredDebtIssuanceCost |  |  |
Senior secured notes due 2018 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, stated interest rate | 8.00%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member |  |  |  |
Debt, long-term and short-term | 0 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member | 325.0 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member |  |  |
Debt Instrument, Repurchased Face Amount |  |  |  | 325.0 us-gaap_DebtInstrumentRepurchasedFaceAmount / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member | 175.0 us-gaap_DebtInstrumentRepurchasedFaceAmount / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member
Redemption Premium, percentage of par value |  |  |  | 106.061%cdw_RedemptionPremiumpercentageofparvalue / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member | 108.00%cdw_RedemptionPremiumpercentageofparvalue / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member
Extinguishment of Debt, Accrued Interest Paid to Lenders |  |  |  |  | 0.7 cdw_ExtinguishmentOfDebtAccruedInterestPaidToLenders / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member
Gains (Losses) on Extinguishment of Debt | (23.7)us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member | 16.7 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member |  |  |
Extinguishment of Debt, Fees Paid to Lenders | 13.0 cdw_ExtinguishmentOfDebtFeesPaidToLenders / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member | 14.0 cdw_ExtinguishmentOfDebtFeesPaidToLenders / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member |  |  |
Extinguishment of Debt, Make-whole Interest Payment | 6.7 cdw_ExtinguishmentofDebtMakewholeInterestPayment / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member |  |  |  |
Write off of Deferred Debt Issuance Cost | $ 4.0 us-gaap_WriteOffOfDeferredDebtIssuanceCost / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member | $ 2.7 us-gaap_WriteOffOfDeferredDebtIssuanceCost / us-gaap_LongtermDebtTypeAxis = cdw_SeniorSecuredNotesDue2018Member |  |  |

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- Definition Extinguishment of Debt, Fees Paid to Lenders + References No definition available. + Details
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- Definition Redemption Premium, percentage of par value + References No definition available. + Details
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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
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -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(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Details
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- Definition Face (par) amount of the original debt instrument that was repurchased. + References No definition available. + 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 Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 + Details
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- Details
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