ASSETS HELD FOR SALE - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2023 USD ($) property franchise dealership_location collisionCenter	Dec. 31, 2022 USD ($) property franchise dealership_location	Dec. 31, 2021 USD ($)
Long Lived Assets Held-for-sale [Line Items]
Assets held for sale	$ 340.1	$ 18.7
Liabilities associated with assets held for sale	$ 2.1	$ 10.5
Number of franchise, sold (in franchises) \| franchise	1	18
Number of dealership locations, sold (in dealership locations) \| dealership_location	1	16
Number of collision centers, sold (in collision centers) \| collisionCenter	3
Gain on divestitures	$ 13.5	$ 207.1	$ 8.0
Held-for-sale
Long Lived Assets Held-for-sale [Line Items]
Number of real estate properties \| franchise	11	1
Assets held for sale		$ 29.1
Liabilities associated with assets held for sale		$ 10.5
Number of dealership locations acquired (in dealership locations) \| dealership_location	11	1
Held-for-sale \| Real Estate Not Currently Used in Operations
Long Lived Assets Held-for-sale [Line Items]
Number of real estate properties \| property	1	1
Assets held for sale	$ 342.2
Liabilities associated with assets held for sale	$ 2.1

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Number of Collision Centers, Sold

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Amount of assets held-for-sale that are not part of a disposal group.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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Amount classified as liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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The number of real estate properties owned as of the balance sheet date.

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