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Business Acquisitions and Dispositions - Additional Information (Detail) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2014 USD ($) Franchise | Sep. 30, 2015 USD ($) Franchise | Sep. 30, 2014 USD ($) Franchise
Business Acquisition [Line Items] |  |  |
Number of franchise acquired |  | 0 |
Combined aggregate purchase price of franchise | $ |  |  | $ 15.3
Number of franchises disposed | 2 | 1 | 5
Cash generated from disposition | $ | $ 14.9 | $ 1.3 | $ 30.1
Mid-line Import Franchise [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Number of franchise acquired | 1 |  |
Luxury Franchise [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Number of franchise acquired |  |  | 1

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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477 + Details
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