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Acquisitions and Dispositions (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018 USD ($) franchise dealership	Sep. 30, 2017 USD ($) franchise dealership
Acquisitions and Dispositions (Textual) [Abstract]
Aggregate consideration paid | $	$ 140.4	$ 120.2
Cash received in acquisition | $	$ 5.1	$ 11.2
United Kingdom
Acquisitions and Dispositions (Textual) [Abstract]
Number of dealerships acquired | dealership	5	12
Number of franchises acquired	8	14
Number of dealerships opened | dealership		1
Number of franchises awarded	1	1
Number of franchises disposed	1
United States
Acquisitions and Dispositions (Textual) [Abstract]
Number of dealerships acquired | dealership	4	3
Number of franchises acquired	4	4
Number of dealerships opened | dealership		1
Number of franchises awarded		1
Number of dealerships disposed | dealership	2
Number of franchises disposed	3
Brazil
Acquisitions and Dispositions (Textual) [Abstract]
Number of dealerships acquired | dealership	1
Number of franchises acquired	1
Number of dealerships disposed | dealership		2
Number of franchises disposed		2

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Number of dealerships acquired.

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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

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-Publisher FASB
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-Topic 805
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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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