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- Definition

Cash Availability, Percentage of Borrowing Base

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No definition available.

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- Definition

For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) and premiums that will be charged against earnings over the life of the debt instruments to which such costs and premiums pertain.

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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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Minimum Liquidity Condition, Amount

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Minimum Liquidity Condition, Cash Availability

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- Definition

Variable Interest Rate Margin

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No definition available.

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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.

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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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

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No definition available.

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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		6 Months Ended
Long-Term Debt - Revolving Loan (Details) £ in Millions	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 GBP (£)	Jun. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Carrying value						$ 3,259,900,000	$ 3,255,900,000
Net loss on extinguishments of long-term debt	$ 0	$ 0	$ 0	$ 57,400,000
CDW UK term loan
Debt Instrument [Line Items]
Carrying value					£ 56	$ 74,000,000	75,700,000
Variable interest rate margin					1.40%	1.40%
Deferred finance costs, net and unamortized premium					£ 1	$ 1,000,000
Senior secured asset-based revolving credit facility
Debt Instrument [Line Items]
Carrying value						0	$ 0
Undrawn letters of credit						1,000,000
Borrowing base						1,800,000,000
Additional borrowing capacity						1,100,000,000
Cash availability, minimum liquidity						$ 125,000,000
Cash availability, percentage of borrowing base					10.00%	10.00%
Minimum liquidity, amount						$ 100,000,000
Net loss on extinguishments of long-term debt				1,000,000
Deferred finance costs, net and unamortized premium		$ 4,000,000		$ 4,000,000
Debt term				5 years
Minimum \| Senior secured asset-based revolving credit facility
Debt Instrument [Line Items]
Consolidated fixed charge coverage ratio					1.00	1.00
Federal Funds Effective Swap Rate \| Senior secured asset-based revolving credit facility
Debt Instrument [Line Items]
Basis spread on variable rate (as percent)			0.50%
London Interbank Offered Rate (LIBOR) \| Senior secured asset-based revolving credit facility
Debt Instrument [Line Items]
Basis spread on variable rate (as percent)			1.00%
Accounts Payable, Inventory Financing \| Senior secured asset-based revolving credit facility
Debt Instrument [Line Items]
Amount owed under Revolving loan financing agreement						$ 357,000,000
LIBOR \| London Interbank Offered Rate (LIBOR) \| Minimum \| Senior secured asset-based revolving credit facility
Debt Instrument [Line Items]
Variable interest rate margin					1.25%	1.25%
LIBOR \| London Interbank Offered Rate (LIBOR) \| Maximum \| Senior secured asset-based revolving credit facility
Debt Instrument [Line Items]
Variable interest rate margin					1.75%	1.75%
ABR \| Base Rate \| Minimum \| Senior secured asset-based revolving credit facility
Debt Instrument [Line Items]
Variable interest rate margin					0.25%	0.25%
ABR \| Base Rate \| Maximum \| Senior secured asset-based revolving credit facility
Debt Instrument [Line Items]
Variable interest rate margin					0.75%	0.75%