DISCONTINUED OPERATIONS AND OTHER DIVESTITURES - Brazil Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
NET INCOME (LOSS) — DISCONTINUED OPERATIONS	$ 0.2	$ (3.4)	$ (0.1)	$ (1.6)
Brazil \| Held-for-sale
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
REVENUE	0.0	101.9	0.0	190.2
COST OF SALES	0.0	88.1	0.0	164.2
GROSS PROFIT	0.0	13.8	0.0	26.1
Selling, general and administrative expenses	0.1	10.6	0.9	19.3
Depreciation and amortization expense	0.0	0.5	0.0	0.9
Asset impairments	0.0	6.3	0.0	6.3
LOSS FROM OPERATIONS — DISCONTINUED OPERATIONS	(0.1)	(3.6)	(0.9)	(0.5)
Floorplan interest expense	0.0	0.7	0.0	1.4
Other interest income, net	(0.7)	(0.3)	(1.4)	(0.4)
INCOME (LOSS) BEFORE INCOME TAXES — DISCONTINUED OPERATIONS	0.5	(4.0)	0.4	(1.5)
Provision (benefit) for income taxes	0.3	(0.6)	0.5	0.1
NET INCOME (LOSS) — DISCONTINUED OPERATIONS	0.2	(3.4)	(0.1)	(1.6)
Brazil \| Held-for-sale \| New vehicle retail sales
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
REVENUE	0.0	60.4	0.0	109.0
COST OF SALES	0.0	54.7	0.0	98.5
Brazil \| Held-for-sale \| Used vehicle retail sales
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
REVENUE	0.0	21.8	0.0	44.0
COST OF SALES	0.0	20.6	0.0	41.2
Brazil \| Held-for-sale \| Used vehicle wholesale sales
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
REVENUE	0.0	4.8	0.0	10.1
COST OF SALES	0.0	4.7	0.0	10.0
Brazil \| Held-for-sale \| Parts and service sales
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
REVENUE	0.0	13.1	0.0	23.8
COST OF SALES	0.0	8.1	0.0	14.5
Brazil \| Held-for-sale \| Finance, insurance and other, net
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
REVENUE	$ 0.0	$ 1.8	$ 0.0	$ 3.3

Disposal Group, Including Discontinued Operation, Other Interest Income

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Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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