Summary of Significant Accounting Policies - Additional Information (Detail) |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2015 |
Jun. 30, 2014 |
Jun. 30, 2015 |
Jun. 30, 2014 |
Dec. 31, 2014 |
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| Significant Accounting Policies [Line Items] | |||||
| Percentage of dealership that is accounted for under the equity method | 50.00% | 50.00% | 50.00% | ||
| Effective tax rate from continuing operations | 39.00% | 39.70% | 39.00% | 39.00% | |
| Minimum [Member] | |||||
| Significant Accounting Policies [Line Items] | |||||
| Expected effective tax rate for continuing operations Range | 38.00% | ||||
| Maximum [Member] | |||||
| Significant Accounting Policies [Line Items] | |||||
| Expected effective tax rate for continuing operations Range | 40.00% | ||||
| X | ||||||||||
- Definition Effective income tax rate continuing operations future period . No definition available.
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- Definition Significant accounting policies. No definition available.
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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