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- Definition

Cash Availability, Percentage of Borrowing Base

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No definition available.

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- Definition

Fixed Charge Coverage Ratio

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- Definition

Line of Credit Facility, Borrowing Base

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No definition available.

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- Definition

Line Of Credit Facility, Maximum Aggregate Increase

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No definition available.

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- Definition

Margin on Borrowings, Reduced Interest Rate from Refinancing in bps

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No definition available.

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- Definition

Minimum Liquidity Condition, Amount

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- Definition

Minimum Liquidity Condition, Cash Availability

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- Definition

Revolving Loan financing agreement

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Long-Term Debt -Revolving Loan (Details) £ in Millions	3 Months Ended
Long-Term Debt -Revolving Loan (Details) £ in Millions	Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2017 GBP (£)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Margin on Borrowings, Reduced Interest Rate from Refinancing in bps			25	25
Net loss on extinguishments of long-term debt	$ (57,400,000)	$ 0
Debt Issuance Costs, Gross				$ 2,000,000
Debt, short-term and long-term				3,303,100,000	$ 3,267,800,000
Borrowing Base				4,000,000
CDW UK Term Loan [Member]
Debt Instrument [Line Items]
Debt, short-term and long-term			£ 56.0	70,200,000	69,100,000
Revolving Loan [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				1,450,000,000	1,250,000,000
Debt, short-term and long-term				38,000,000	0
Undrawn letters of credit				1,000,000
Borrowing Base				1,409,000,000
Line of Credit Facility, Remaining Borrowing Capacity				963,000,000
Minimum Liquidity Condition, Cash Availability				$ 125,000,000
Cash Availability, Percentage of Borrowing Base			10.00%	10.00%
Minimum Liquidity Condition, Amount				$ 100,000,000
Debt Instrument, Basis Spread on Variable Rate	1.00%
Line Of Credit Facility, Maximum Aggregate Increase				300,000,000
CDW UK Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt, short-term and long-term				0	0
Line of Credit Facility, Remaining Borrowing Capacity			£ 50.0	63,000,000
Accounts Payable, Inventory Financing [Member]
Debt Instrument [Line Items]
Revolving Loan inventory financing agreement				427,200,000	$ 558,300,000
Accounts Payable, Inventory Financing [Member] \| Revolving Loan [Member]
Debt Instrument [Line Items]
Amount owed under Revolving loan financing agreement				$ 407,000,000
Minimum [Member] \| Revolving Loan [Member]
Debt Instrument [Line Items]
Fixed Charge Coverage Ratio			1	1
Federal Funds Effective Swap Rate [Member] \| Revolving Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	5000.00%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member] \| Revolving Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.50%
London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member] \| Revolving Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.00%
Base Rate [Member] \| Minimum [Member] \| Revolving Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.50%
Base Rate [Member] \| Maximum [Member] \| Revolving Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Revolving Loan [Member]
Debt Instrument [Line Items]
Net loss on extinguishments of long-term debt	$ 1,000,000
Term Loan [Member]
Debt Instrument [Line Items]
Net loss on extinguishments of long-term debt	$ 14,000,000