GOODWILL AND FRANCHISE VALUE - Schedule of Goodwill (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2025	Dec. 31, 2024
Goodwill [Roll Forward]
Beginning balance	$ 2,115.5	$ 1,930.6
Adjustments to purchase price allocations		47.7
Additions through acquisitions	347.9	167.0
Reductions through disposals	(39.2)	(22.1)
Currency translation	15.9	(7.7)
Ending balance	2,440.1	2,115.5
2023 Acquisitions
Goodwill [Roll Forward]
Additions through acquisitions		146.6
2024 Acquisitions
Goodwill [Roll Forward]
Additions through acquisitions	347.9	20.4
Vehicle Operations
Goodwill [Roll Forward]
Beginning balance	2,099.3	1,913.0
Adjustments to purchase price allocations		47.7
Additions through acquisitions	347.9	167.0
Reductions through disposals	(39.2)	(22.1)
Currency translation	15.4	(6.3)
Ending balance	2,423.4	2,099.3
Financing Operations
Goodwill [Roll Forward]
Beginning balance	16.2	17.6
Adjustments to purchase price allocations		0.0
Additions through acquisitions	0.0	0.0
Reductions through disposals	0.0	0.0
Currency translation	0.5	(1.4)
Ending balance	$ 16.7	$ 16.2

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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