Debt Instrument, Margin On Borrowings, Reduced Interest Rate From Refinancing

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.

+ References

No definition available.

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- Definition

Net Leverage Ratio

+ References

No definition available.

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- Definition

Variable Interest Rate Margin

+ References

No definition available.

+ Details

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- Definition

Write Off Of Deferred Debt Discount

+ References

No definition available.

+ Details

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- Definition

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

+ References

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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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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.

+ References

No definition available.

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- Definition

Amount of the required periodic payments applied to principal.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	debit
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

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-Publisher FASB
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- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

+ References

No definition available.

+ Details

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- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Long-Term Debt - Term Loan (Details) £ in Millions, $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2018 GBP (£)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Apr. 03, 2018	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Carrying value						$ 3,238.2		$ 3,255.9
Net loss on extinguishments of long-term debt		$ 0.0	$ 0.0	$ 0.0	$ 57.4
Senior secured term loan facility
Debt Instrument [Line Items]
Reduction in interest margins from debt amended							0.25%
Net leverage ratio	2.33					2.33	3.75
Carrying value						$ 1,456.9		$ 1,468.0	$ 1,500.0
Deferred financing costs						$ 3.0
Quarterly principal installment				$ 4.0
Net loss on extinguishments of long-term debt					14.0
Write off of deferred financing costs					5.0
Write off of deferred debt discount					9.0
Payments of debt issuance costs					$ 2.0
Interest Rate	3.80%					3.80%		3.70%
CDW UK term loan
Debt Instrument [Line Items]
Variable interest rate margin	1.40%					1.40%
Carrying value	£ 51					$ 66.0		$ 75.7
Deferred finance costs, net and unamortized premium	1					$ 1.0
Repayments of debt	£ 5	$ 7.0
Interest Rate	2.29%					2.29%		1.90%
CDW UK Revolving Credit Facility
Debt Instrument [Line Items]
Carrying value	£ 5					$ 7.0
Total borrowing capacity	£ 50					$ 65.0
LIBOR \| Senior secured term loan facility
Debt Instrument [Line Items]
Variable interest rate margin							1.75%
ABR \| Senior secured term loan facility
Debt Instrument [Line Items]
Variable interest rate margin							0.75%
Federal Funds Effective Swap Rate \| Senior secured term loan facility
Debt Instrument [Line Items]
Basis spread on variable rate (as percent)				0.50%