v2.4.1.9

Schedule of Goodwill by Segment (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended |
--- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Goodwill [Roll Forward] |  |  |  |  |  |
Goodwill, Gross | $ 4,174.1 us-gaap_GoodwillGross |  | $ 4,163.1 us-gaap_GoodwillGross |  |  |
Period Increase (Decrease) | (2.7)us-gaap_GoodwillPeriodIncreaseDecrease |  | 11.0 us-gaap_GoodwillPeriodIncreaseDecrease |  |  |
Translation adjustment | (2.7)us-gaap_GoodwillTranslationAdjustments |  | (2.1)us-gaap_GoodwillTranslationAdjustments |  |  |
Contingent consideration related to pre-2009 business combination |  |  | 13.1 cdw_Contingentconsiderationrelatedtopre2009businesscombination | [1] |  |
Goodwill, Gross | 4,171.4 us-gaap_GoodwillGross |  | 4,174.1 us-gaap_GoodwillGross |  |  |
Accumulated impairment charges | (1,953.8)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss |  | (1,953.8)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss |  | (1,953.8)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss |
Goodwill | 2,217.6 us-gaap_Goodwill |  | 2,220.3 us-gaap_Goodwill |  | 2,209.3 us-gaap_Goodwill |
Corporate [Member] |  |  |  |  |  |
Goodwill [Roll Forward] |  |  |  |  |  |
Goodwill, Gross | 2,803.2 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 2,794.4 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  |  |
Period Increase (Decrease) | 0 us-gaap_GoodwillPeriodIncreaseDecrease / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 8.8 us-gaap_GoodwillPeriodIncreaseDecrease / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  |  |
Translation adjustment | 0 us-gaap_GoodwillTranslationAdjustments / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 0 us-gaap_GoodwillTranslationAdjustments / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  |  |
Contingent consideration related to pre-2009 business combination |  |  | 8.8 cdw_Contingentconsiderationrelatedtopre2009businesscombination / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember | [1] |  |
Goodwill, Gross | 2,803.2 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 2,803.2 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  |  |
Accumulated impairment charges | (1,571.4)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | (1,571.4)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | (1,571.4)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |
Goodwill | 1,231.8 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 1,231.8 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 1,223.0 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |
Public [Member] |  |  |  |  |  |
Goodwill [Roll Forward] |  |  |  |  |  |
Goodwill, Gross | 1,265.4 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 1,261.4 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  |  |
Period Increase (Decrease) | 0 us-gaap_GoodwillPeriodIncreaseDecrease / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 4.0 us-gaap_GoodwillPeriodIncreaseDecrease / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  |  |
Translation adjustment | 0 us-gaap_GoodwillTranslationAdjustments / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 0 us-gaap_GoodwillTranslationAdjustments / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  |  |
Contingent consideration related to pre-2009 business combination |  |  | 4.0 cdw_Contingentconsiderationrelatedtopre2009businesscombination / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember | [1] |  |
Goodwill, Gross | 1,265.4 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 1,265.4 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  |  |
Accumulated impairment charges | (354.1)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | (354.1)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | (354.1)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |
Goodwill | 911.3 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 911.3 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 907.3 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |
Other Segments [Member] |  |  |  |  |  |
Goodwill [Roll Forward] |  |  |  |  |  |
Goodwill, Gross | 105.5 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2] | 107.3 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2] |  |
Period Increase (Decrease) | (2.7)us-gaap_GoodwillPeriodIncreaseDecrease / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2] | (1.8)us-gaap_GoodwillPeriodIncreaseDecrease / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2] |  |
Translation adjustment | (2.7)us-gaap_GoodwillTranslationAdjustments / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2] | (2.1)us-gaap_GoodwillTranslationAdjustments / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2] |  |
Contingent consideration related to pre-2009 business combination |  |  | 0.3 cdw_Contingentconsiderationrelatedtopre2009businesscombination / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [1],[2] |  |
Goodwill, Gross | 102.8 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2] | 105.5 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2] |  |
Accumulated impairment charges | (28.3)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2] | (28.3)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2] | (28.3)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2]
Goodwill | 74.5 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2] | 77.2 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2] | 79.0 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2]
Kelway Operating Segment [Member] |  |  |  |  |  |
Goodwill [Roll Forward] |  |  |  |  |  |
Goodwill | $ 0 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cdw_KelwayOperatingSegmentMember |  | $ 0 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cdw_KelwayOperatingSegmentMember |  | $ 0 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cdw_KelwayOperatingSegmentMember |
[1] | During 2013, the Company recorded a $13.1 million net-of-tax addition to goodwill in connection with the settlement of the MPK Coworker Incentive Plan II and related charitable contribution. The charitable contribution was accounted for as additional purchase price (goodwill) in accordance with pre-2009 business combinations accounting guidance. See Note 10 for additional discussion of this transaction.
[2] | Other is comprised of CDW Advanced Services, Canada, and Kelway reporting units. There is no goodwill attributable to the Kelway reporting unit.

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