Long-Term Debt (Restrictions and Covenants) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Credit Facility Due 2019 [Member]
Debt Instrument [Line Items]
Capitalization ratio, actual	59.20%
Leverage ratio, requirement	3.75
Leverage ratio, actual	2.30
Capitalization ratio, requirement	70.00%
The maximum threshold of letters of credit excluded from the leverage ratio calculation	$ 150,000,000
Capitalization ratio calculation, additions to shareholders' equity	$ 1,530,000,000
Credit facility due 2016 [Member]
Debt Instrument [Line Items]
Capitalization ratio, requirement		65.00%

Under the credit agreement, the amount added to shareholders' equity in the calculation of the capitalization ratio.

No definition available.

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- Definition

Under the terms of the credit agreement, the maximum amount of letters of credit excluded from the definition of debt used in the calculation of the leverage ratio.

+ References

No definition available.

+ Details

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- Definition

The actual debt covenant capitalization ratio as defined in the credit agreement as principally reflecting vehicle floorplan payable and non-vehicle debt divided by the company's total capitalization including vehicle floorplan payable and certain adjustments. Under the credit agreement, the company is required to remain in compliance with a maximum capitalization ratio.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The actual debt covenant leverage ratio as defined in the credit agreement as principally reflecting non-vehicle debt divided by a contractually defined measure of earnings with certain adjustments. Under the credit agreement, the company is required to remain in compliance with a maximum leverage ratio.

+ References

No definition available.

+ Details

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- Definition

The maximum capitalization ratio required under the company's credit agreement, which is a contractually defined amount principally reflecting vehicle floorplan payable and non-vehicle debt divided by the company's total capitalization including vehicle floorplan payable and certain adjustments.

+ References

No definition available.

+ Details

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- Definition

The maximum leverage ratio required under the company's credit agreement, which is a contractually defined amount principally reflecting non-vehicle debt divided by a contractually defined measure of earnings with certain adjustments.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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