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Intangible Franchise Rights and Goodwill - Narrative (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 USD ($) dealership | Dec. 31, 2017 USD ($) franchise dealership | Dec. 31, 2016 franchise | Dec. 31, 2016 dealership
Countries and States [Line Items] |  |  |  |
Impairments | $ | $ 38,740 | $ 19,332 |  |
Number of dealerships disposed | franchise |  | 3 |  |
U.S. |  |  |  |
Countries and States [Line Items] |  |  |  |
Number of dealerships acquired | 4 | 3 |  |
Impairments | $ | $ 38,255 | $ 12,588 |  |
Number of dealerships disposed | 2 |  |  |
U.K. |  |  |  |
Countries and States [Line Items] |  |  |  |
Number of dealerships acquired | 5 | 12 |  | 12
Impairments | $ | $ 485 | $ 0 |  |
Number of dealerships disposed |  | 1 |  |
Brazil |  |  |  |
Countries and States [Line Items] |  |  |  |
Number of dealerships acquired | 1 |  | 1 | 1
Impairments | $ | $ 0 | $ 6,744 |  |
Number of dealerships disposed |  | 2 |  |

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- Definition Number of dealerships acquired. + References No definition available. + Details
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- Definition The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275 + Details
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