DISCONTINUED OPERATIONS AND OTHER DIVESTITURES - Brazil Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
NET LOSS — DISCONTINUED OPERATIONS	$ (0.2)	$ (1.3)	$ (0.3)	$ (2.9)
Brazil \| Held-for-sale
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
REVENUE	0.0	0.0	0.0	190.2
COST OF SALES	0.0	0.0	0.0	164.2
GROSS PROFIT	0.0	0.0	0.0	26.1
Selling, general and administrative expenses	0.7	(4.6)	1.6	14.8
Depreciation and amortization expense	0.0	0.0	0.0	0.9
Asset impairments	0.0	0.1	0.0	6.3
(LOSS) INCOME FROM OPERATIONS — DISCONTINUED OPERATIONS	(0.7)	4.5	(1.6)	4.0
Floorplan interest expense	0.0	0.0	0.0	1.4
Other interest income, net	(0.7)	(0.7)	(2.0)	(1.1)
Other expenses	0.0	1.5	0.0	1.5
(LOSS) INCOME BEFORE INCOME TAXES — DISCONTINUED OPERATIONS	0.0	3.7	0.4	2.2
Provision for income taxes	0.2	5.0	0.7	5.1
NET LOSS — DISCONTINUED OPERATIONS	(0.2)	(1.3)	(0.3)	(2.9)
Brazil \| Held-for-sale \| New vehicle retail sales
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
REVENUE	0.0	0.0	0.0	109.0
COST OF SALES	0.0	0.0	0.0	98.5
Brazil \| Held-for-sale \| Used vehicle retail sales
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
REVENUE	0.0	0.0	0.0	44.0
COST OF SALES	0.0	0.0	0.0	41.2
Brazil \| Held-for-sale \| Used vehicle wholesale sales
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
REVENUE	0.0	0.0	0.0	10.1
COST OF SALES	0.0	0.0	0.0	10.0
Brazil \| Held-for-sale \| Parts and service sales
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
REVENUE	0.0	0.0	0.0	23.8
COST OF SALES	0.0	0.0	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	$ 0.0	$ 0.0	$ 3.3

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