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Acquisitions (Details) - store	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Premium Luxury Dealership [Member]
Business Acquisition [Line Items]
Number of stores purchased		1
Collision Centers [Member]
Business Acquisition [Line Items]
Number of stores purchased		4
California | Premium Luxury Dealership [Member]
Business Acquisition [Line Items]
Number of stores purchased	1
Maryland | Collision Centers [Member]
Business Acquisition [Line Items]
Number of stores purchased	1
Texas | Collision Centers [Member]
Business Acquisition [Line Items]
Number of stores purchased	1

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- Definition

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+ References

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- Definition

The number of businesses acquired by the entity during the period.

+ References

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