Business Combinations - Narrative (Details) $ in Millions	9 Months Ended
Sep. 30, 2024 USD ($) franchise dealership center
Business Acquisition [Line Items]
Revenue from date of acquisition of companies acquired \| $	$ 812.2
Pre-tax income from date of acquisition of companies acquired \| $	$ 18.2
U.K. \| Retail automotive dealership \| Franchised Dealerships
Business Acquisition [Line Items]
Number of franchises acquired	16
ITALY \| Retail automotive dealership \| Franchised Dealerships
Business Acquisition [Line Items]
Number of franchises acquired	2
AUSTRALIA \| Retail automotive dealership \| Franchised Dealerships
Business Acquisition [Line Items]
Number of franchises acquired	2
AUSTRALIA \| Retail automotive dealership \| CarShop Used Vehicle Dealerships
Business Acquisition [Line Items]
Number of franchises acquired \| dealership	1
U.S. \| Retail automotive dealership \| Franchised Dealerships
Business Acquisition [Line Items]
Number of franchises acquired	2
U.S. \| Retail automotive dealership \| Franchised Dealerships \| Ford
Business Acquisition [Line Items]
Number of franchises acquired	2
U.S. \| Retail automotive dealership \| Franchised Dealerships \| Ford \| Nonrelated Party
Business Acquisition [Line Items]
Number of franchises acquired	1
U.S. \| Retail commercial truck dealership \| Franchised Dealerships \| Full-Service Dealership
Business Acquisition [Line Items]
Number of franchises acquired \| dealership	3
U.S. \| Retail commercial truck dealership \| Franchised Dealerships \| Collision Center
Business Acquisition [Line Items]
Number of franchises acquired \| dealership	2
Canada \| Retail automotive dealership \| Service and parts
Business Acquisition [Line Items]
Number of franchises acquired \| center	2
Canada \| Retail commercial truck dealership \| Franchised Dealerships \| Full-Service Dealership
Business Acquisition [Line Items]
Number of franchises acquired \| dealership	3

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-Topic 805
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-Section 50
-Paragraph 5
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-Publisher FASB
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