v2.4.1.9

Selected Quarterly Financial Results (Details) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
IPO Related Expenses |  |  |  |  |  |  |  |  | $ 74,100,000 cdw_IPORelatedExpenses |  |  |  |  |  |  |  |  |  |  |
Revenue, Net | 3,050,100,000 us-gaap_SalesRevenueNet |  | 3,266,100,000 us-gaap_SalesRevenueNet |  | 3,106,000,000 us-gaap_SalesRevenueNet |  | 2,652,300,000 us-gaap_SalesRevenueNet |  | 2,713,300,000 us-gaap_SalesRevenueNet |  | 2,864,300,000 us-gaap_SalesRevenueNet |  | 2,779,300,000 us-gaap_SalesRevenueNet |  | 2,411,700,000 us-gaap_SalesRevenueNet |  | 12,074,500,000 us-gaap_SalesRevenueNet | 10,768,600,000 us-gaap_SalesRevenueNet |  | 10,128,200,000 us-gaap_SalesRevenueNet
Gross Profit | 491,900,000 us-gaap_GrossProfit |  | 507,300,000 us-gaap_GrossProfit |  | 496,900,000 us-gaap_GrossProfit |  | 425,200,000 us-gaap_GrossProfit |  | 448,300,000 us-gaap_GrossProfit |  | 458,400,000 us-gaap_GrossProfit |  | 451,600,000 us-gaap_GrossProfit |  | 402,000,000 us-gaap_GrossProfit |  | 1,921,300,000 us-gaap_GrossProfit | 1,760,300,000 us-gaap_GrossProfit |  | 1,669,600,000 us-gaap_GrossProfit
Income (loss) from operations | 164,300,000 us-gaap_OperatingIncomeLoss |  | 184,700,000 us-gaap_OperatingIncomeLoss |  | 188,200,000 us-gaap_OperatingIncomeLoss |  | 135,800,000 us-gaap_OperatingIncomeLoss |  | 142,000,000 us-gaap_OperatingIncomeLoss | [1] | 92,900,000 us-gaap_OperatingIncomeLoss | [1] | 153,600,000 us-gaap_OperatingIncomeLoss | [1] | 120,100,000 us-gaap_OperatingIncomeLoss | [1] | 673,000,000 us-gaap_OperatingIncomeLoss | 508,600,000 us-gaap_OperatingIncomeLoss | [2] | 510,600,000 us-gaap_OperatingIncomeLoss
Net income (loss) | 51,800,000 us-gaap_NetIncomeLoss |  | 55,600,000 us-gaap_NetIncomeLoss |  | 86,600,000 us-gaap_NetIncomeLoss |  | 50,900,000 us-gaap_NetIncomeLoss |  | 60,000,000 us-gaap_NetIncomeLoss | [1] | (2,200,000)us-gaap_NetIncomeLoss | [1] | 46,700,000 us-gaap_NetIncomeLoss | [1] | 28,300,000 us-gaap_NetIncomeLoss | [1] | 244,900,000 us-gaap_NetIncomeLoss | 132,800,000 us-gaap_NetIncomeLoss |  | 119,000,000 us-gaap_NetIncomeLoss
Basic | $ 0.30 us-gaap_EarningsPerShareBasic | [3] | $ 0.33 us-gaap_EarningsPerShareBasic | [3] | $ 0.51 us-gaap_EarningsPerShareBasic | [3] | $ 0.30 us-gaap_EarningsPerShareBasic | [3] | $ 0.35 us-gaap_EarningsPerShareBasic | [1],[3] | $ (0.01)us-gaap_EarningsPerShareBasic | [1],[3] | $ 0.32 us-gaap_EarningsPerShareBasic | [1],[3] | $ 0.19 us-gaap_EarningsPerShareBasic | [1],[3] | $ 1.44 us-gaap_EarningsPerShareBasic | $ 0.85 us-gaap_EarningsPerShareBasic |  | $ 0.82 us-gaap_EarningsPerShareBasic
Diluted | $ 0.30 us-gaap_EarningsPerShareDiluted | [3] | $ 0.32 us-gaap_EarningsPerShareDiluted | [3] | $ 0.50 us-gaap_EarningsPerShareDiluted | [3] | $ 0.30 us-gaap_EarningsPerShareDiluted | [3] | $ 0.35 us-gaap_EarningsPerShareDiluted | [1],[3] | $ (0.01)us-gaap_EarningsPerShareDiluted | [1],[3] | $ 0.32 us-gaap_EarningsPerShareDiluted | [1],[3] | $ 0.19 us-gaap_EarningsPerShareDiluted | [1],[3] | $ 1.42 us-gaap_EarningsPerShareDiluted | $ 0.84 us-gaap_EarningsPerShareDiluted |  | $ 0.82 us-gaap_EarningsPerShareDiluted
Corporate [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue, Net | 1,691,000,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 1,622,700,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 1,656,200,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 1,505,600,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 1,553,000,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 1,465,800,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 1,537,400,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 1,403,900,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  |  |  |  |
Corporate [Member] | Medium/Large [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue, Net | 1,440,300,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_MediumLargeMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 1,374,800,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_MediumLargeMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 1,395,400,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_MediumLargeMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 1,274,800,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_MediumLargeMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 1,322,300,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_MediumLargeMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember | [4] | 1,241,300,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_MediumLargeMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember | [4] | 1,308,500,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_MediumLargeMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember | [4] | 1,180,500,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_MediumLargeMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember | [4] |  |  |  |
Corporate [Member] | Small Business [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue, Net | 250,700,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_SmallBusinessMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 247,900,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_SmallBusinessMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 260,800,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_SmallBusinessMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 230,800,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_SmallBusinessMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember |  | 230,700,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_SmallBusinessMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember | [4] | 224,500,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_SmallBusinessMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember | [4] | 228,900,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_SmallBusinessMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember | [4] | 223,400,000 us-gaap_SalesRevenueNet / cdw_CorporateAxis = cdw_SmallBusinessMember / us-gaap_StatementBusinessSegmentsAxis = cdw_CorporateSegmentMember | [4] |  |  |  |
Public [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue, Net | 1,169,100,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 1,468,800,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 1,271,600,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 969,900,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 990,500,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 1,244,600,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 1,082,600,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 846,800,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  |  |  |  |
Public [Member] | Government [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue, Net | 440,800,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_GovernmentSegmentMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 441,300,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_GovernmentSegmentMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 313,100,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_GovernmentSegmentMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 254,200,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_GovernmentSegmentMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 327,300,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_GovernmentSegmentMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 375,300,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_GovernmentSegmentMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 295,700,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_GovernmentSegmentMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 252,300,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_GovernmentSegmentMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  |  |  |  |
Public [Member] | Education [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue, Net | 342,600,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_EducationMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 632,800,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_EducationMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 527,000,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_EducationMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 321,600,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_EducationMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 282,800,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_EducationMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 513,400,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_EducationMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 420,600,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_EducationMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 232,200,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_EducationMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  |  |  |  |
Public [Member] | Healthcare [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue, Net | 385,700,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_HealthcareMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 394,700,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_HealthcareMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 431,500,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_HealthcareMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 394,100,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_HealthcareMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 380,400,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_HealthcareMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 355,900,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_HealthcareMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 366,300,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_HealthcareMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  | 362,300,000 us-gaap_SalesRevenueNet / cdw_PublicAxis = cdw_HealthcareMember / us-gaap_StatementBusinessSegmentsAxis = cdw_PublicMember |  |  |  |  |
Other [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue, Net | 190,000,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember |  | 174,600,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember |  | 178,200,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember |  | 176,800,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember |  | 169,800,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember |  | 153,900,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember |  | 159,300,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember |  | 161,000,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember |  | 719,600,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 644,000,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember |  | 592,400,000 us-gaap_SalesRevenueNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Income (loss) from operations |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 32,900,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | $ 27,200,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | [2] | $ 18,600,000 us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
[1] | (3)The third quarter of 2013 included pre-tax IPO-related charges of $74.1 million. See Note 9 for additional discussion of the IPO.
[2] | (1) Includes $75.0 million of IPO- and secondary-offering related expenses, as follows: Corporate $26.4 million; Public $14.4 million; Other $3.6 million; and Headquarters $30.6 million.
[3] | (1) Basic and diluted net income (loss) per share are computed independently for each of the quarters presented. Therefore, the sum of quarterly basic and diluted per share information may not equal annual basic and diluted net income (loss) per share.
[4] | (2)Net sales for the corporate channels (medium/large and small business) have been restated for all periods presented above to conform with the new corporate hierarchy presented for first quarter of 2014.

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