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Business Acquisitions and Dispositions - Revenues and Other Activities Associated with Disposed Dealerships That Remain in Continuing Operations (Detail) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2017 | Mar. 31, 2016
Business Combinations [Abstract] |  |
Income (loss) from operations | $ (27) | $ (31)
Gain (loss) on disposal | (24) | (48)
Pre-tax income (loss) | $ (51) | (79)
Total revenues |  | $ 14

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- Definition Disposal group not discontinued operation income loss before income tax. + References No definition available. + Details
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- Definition Disposal group not discontinued operation revenue. + References No definition available. + Details
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- Definition Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2443-110228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=64862545&loc=d3e2941-110230 + Details
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