Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Represents the impact on the weighted average interest rate from interest rate swaps for the period.

+ References

No definition available.

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Topic 210
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-Section 55
-Paragraph 7
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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

Fair value of asset associated with financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226003-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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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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Derivatives and Hedging (Details) - USD ($) $ in Millions	12 Months Ended
Derivatives and Hedging (Details) - USD ($) $ in Millions	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015
Forward foreign exchange contracts \| Fair Value, Inputs, Level 2
Derivative
Estimated asset of contracts designated as hedging instruments, fair value		$ 0.3
Estimated liability of contracts designated as hedging instruments, fair value			$ 1.1
Interest Rate Swap Agreements \| Floating Rate Floor Plan Debt
Derivative
Increase in the weighted average interest rate on floor plan borrowings due to the swaps (as a percent)	0.30%
Interest Rate Swap Agreements \| Floating Rate Floor Plan Debt \| LIBOR portion
Derivative
Portion of floating rate floor plan debt fixed by swap agreements	$ 300.0
Interest rate swap, fixed (as a percent)	2.135%
Interest Rate Swap Agreements \| Floating Rate Floor Plan Debt \| Fixed rate portion
Derivative
Portion of floating rate floor plan debt fixed by swap agreements	$ 100.0
Interest rate swap, fixed (as a percent)	1.55%