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Intangible Franchise Rights and Goodwill - Narrative (Details) $ in Thousands	12 Months Ended
	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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Countries and States.

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Number of dealerships acquired.

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Number of Dealerships Disposed

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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

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