Number of full service dealerships acquired.

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

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Business Combinations - Narrative (Details) $ in Millions	12 Months Ended
Business Combinations - Narrative (Details) $ in Millions	Dec. 31, 2023 USD ($) franchise shop center dealership	Dec. 31, 2022 franchise dealership
Business Acquisition [Line Items]
Revenue from date of acquisition of companies acquired \| $	$ 146.6
Pre-tax income from date of acquisition of companies acquired \| $	$ 5.1
Retail automotive dealership \| Franchised Dealerships
Business Acquisition [Line Items]
Number of Businesses Acquired		19
Canada \| Retail commercial truck dealership \| Full-Service Commercial Truck Dealerships
Business Acquisition [Line Items]
Number of Businesses Acquired \| dealership	3
Number of full service dealerships acquired \| dealership		4
Canada \| Retail commercial truck dealership \| Service and Parts Centers
Business Acquisition [Line Items]
Number of Businesses Acquired \| center	2
U.S. \| Retail automotive dealership \| Franchised Dealerships
Business Acquisition [Line Items]
Number of Businesses Acquired	2	4
Italy \| Retail automotive dealership \| Franchised Dealerships
Business Acquisition [Line Items]
Number of Businesses Acquired	2
Italy \| Retail automotive dealership \| Body Shops
Business Acquisition [Line Items]
Number of Businesses Acquired \| shop	1
AUSTRALIA \| Commercial vehicle distribution and other \| Service Centers
Business Acquisition [Line Items]
Number of Businesses Acquired \| center	1
U.K. \| Retail automotive dealership \| Franchised Dealerships
Business Acquisition [Line Items]
Number of Businesses Acquired		15