XML 100 R58.htm IDEA: XBRL DOCUMENT 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 $ 3,192.4us-gaap_DebtInstrumentCarryingAmount        
Gains (Losses) on Extinguishment of Debt 90.7us-gaap_GainsLossesOnExtinguishmentOfDebt 64.0us-gaap_GainsLossesOnExtinguishmentOfDebt 17.2us-gaap_GainsLossesOnExtinguishmentOfDebt    
Write off of Deferred Debt Issuance Cost 12.6us-gaap_WriteOffOfDeferredDebtIssuanceCost 20.1us-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 0us-gaap_DebtInstrumentCarryingAmount
/ us-gaap_LongtermDebtTypeAxis
= cdw_SeniorSecuredNotesDue2018Member
325.0us-gaap_DebtInstrumentCarryingAmount
/ us-gaap_LongtermDebtTypeAxis
= cdw_SeniorSecuredNotesDue2018Member
     
Debt Instrument, Repurchased Face Amount       325.0us-gaap_DebtInstrumentRepurchasedFaceAmount
/ us-gaap_LongtermDebtTypeAxis
= cdw_SeniorSecuredNotesDue2018Member
175.0us-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         0.7cdw_ExtinguishmentOfDebtAccruedInterestPaidToLenders
/ us-gaap_LongtermDebtTypeAxis
= cdw_SeniorSecuredNotesDue2018Member
Gains (Losses) on Extinguishment of Debt (23.7)us-gaap_GainsLossesOnExtinguishmentOfDebt
/ us-gaap_LongtermDebtTypeAxis
= cdw_SeniorSecuredNotesDue2018Member
16.7us-gaap_GainsLossesOnExtinguishmentOfDebt
/ us-gaap_LongtermDebtTypeAxis
= cdw_SeniorSecuredNotesDue2018Member
     
Extinguishment of Debt, Fees Paid to Lenders 13.0cdw_ExtinguishmentOfDebtFeesPaidToLenders
/ us-gaap_LongtermDebtTypeAxis
= cdw_SeniorSecuredNotesDue2018Member
14.0cdw_ExtinguishmentOfDebtFeesPaidToLenders
/ us-gaap_LongtermDebtTypeAxis
= cdw_SeniorSecuredNotesDue2018Member
     
Extinguishment of Debt, Make-whole Interest Payment 6.7cdw_ExtinguishmentofDebtMakewholeInterestPayment
/ us-gaap_LongtermDebtTypeAxis
= cdw_SeniorSecuredNotesDue2018Member
       
Write off of Deferred Debt Issuance Cost $ 4.0us-gaap_WriteOffOfDeferredDebtIssuanceCost
/ us-gaap_LongtermDebtTypeAxis
= cdw_SeniorSecuredNotesDue2018Member
$ 2.7us-gaap_WriteOffOfDeferredDebtIssuanceCost
/ us-gaap_LongtermDebtTypeAxis
= cdw_SeniorSecuredNotesDue2018Member