Business Combinations - Activity (Details)	6 Months Ended
Jun. 30, 2021 item
Business combinations
Number of acquired franchises	1
KCFL
Business combinations
Number of full service dealerships added	4
Number of parts and service centers added	4
Number of collision centers added	2

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.

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