Acquisitions (Details) - store	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Collision Centers [Member]
Business Acquisition [Line Items]
Number of stores purchased	4
Dealerships [Member]
Business Acquisition [Line Items]
Number of stores purchased	1	18

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Period Type:	duration