v2.4.1.9

Shareholders' Equity IPO- and secondary-offering related expenses (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2014 | Dec. 31, 2013
Class of Stock [Line Items] |  |  |  |  |  |  |  |
Secondary-offering related expenses | $ 0.2 cdw_Secondaryofferingrelatedexpenses | $ 0.3 cdw_Secondaryofferingrelatedexpenses | $ 0.5 cdw_Secondaryofferingrelatedexpenses | $ 0.4 cdw_Secondaryofferingrelatedexpenses | $ 1.4 cdw_Secondaryofferingrelatedexpenses | [1] | $ 0.6 cdw_Secondaryofferingrelatedexpenses |
Net proceeds used for termination of management services agreement |  |  |  |  | 0 cdw_Netproceedsusedforterminationofmanagementservicesagreement | [2] | 24.4 cdw_Netproceedsusedforterminationofmanagementservicesagreement | [2]
Other IPO Related Expenses |  |  |  |  |  |  | 2.4 cdw_OtherIPORelatedExpenses | [1]
IPO and Secondary-offering related expenses |  |  |  |  |  |  | 75.0 cdw_IPOandSecondaryofferingrelatedexpenses |
Accelerated share based compensation expense and related employer payroll taxes |  |  |  |  | 0 cdw_Acceleratedsharebasedcompensationexpenseandrelatedemployerpayrolltaxes | [3] | 40.7 cdw_Acceleratedsharebasedcompensationexpenseandrelatedemployerpayrolltaxes | [3]
Charge for payment of RDU Plan cash retention pool |  |  |  |  | 0 cdw_ChargeforpaymentofRDUPlancashretentionpool | [4] | 7.5 cdw_ChargeforpaymentofRDUPlancashretentionpool | [4]
Net proceeds used for termination of Management Services Agreement |  |  |  |  |  |  | $ 24.4 cdw_NetproceedsusedforterminationofManagementServicesAgreement |
[1] | Other expenses include secondary-offering expenses of $1.4 million and $0.6 million for the years ended December 31, 2014 and 2013, respectively.
[2] | Represents the payment of a termination fee to affiliates of the Sponsors in connection with the termination of the management services agreement with such entities.
[3] | See Note 10 for additional discussion of the impact of the IPO on the Company's equity awards.
[4] | See Note 12 for additional discussion of this transaction.

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