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Inventories and Related Notes Payable - Floor Plan - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Inventory Disclosure [Abstract] |  |  |
Average interest rate for new vehicle floor plan facilities, for continuing operations and discontinued operations | 1.86% | 2.02% | 2.39%
Amount recognized as reduction in cost of sales for continuing and discontinued operations | $ 37.9 | $ 33.0 | $ 26.7
Average interest rate for used vehicle floor plan facilities, for continuing operations and discontinued operations | 2.78% | 2.80% | 2.71%

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- Definition Floor plan assistance recognized. + References No definition available. + Details
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- Definition Weighted average interest rate new vehicle floor plan. + References No definition available. + Details
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- Definition Weighted average interest rate used vehicle floor plan. + References No definition available. + Details
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Balance Type: | na
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- Details
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