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Inventories and Related Notes Payable - Floor Plan - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Inventory Disclosure [Abstract] |  |  |
Average interest rate for new vehicle floor plan facilities, for continuing operations and discontinued operations | 1.85% | 1.61% | 1.57%
Amount recognized as reduction in cost of sales for continuing and discontinued operations | $ 45.0 | $ 42.1 | $ 39.7
Average interest rate for used vehicle floor plan facilities, for continuing operations and discontinued operations | 1.78% | 1.72% | 1.80%

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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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- References No definition available. + Details
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