FLOOR PLAN NOTES PAYABLE—NON-TRADE - Consist of (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Floor plan notes payable—new non-trade	$ 1,328.1	$ 613.6
Floor plan notes payable—used non-trade	307.1	0.0
Floor plan notes payable offset account	(44.7)	(613.6)
Total floor plan notes payable—non-trade, net	1,590.6	0.0
Floor plan notes payable—non-trade, liabilities associated with assets held for sale		$ 2.8
Floor plan, notes payable, offset account, additional amount	164.0
Cash and Cash Equivalents
Debt Instrument [Line Items]
Floor plan, notes payable, offset account, additional amount	100.8
Accounts payable and accrued liabilities
Debt Instrument [Line Items]
Floor plan, notes payable, offset account, additional amount	$ 63.2