Unaudited Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Statement of Financial Position [Abstract]
AUTO LOANS RECEIVABLE, allowance for credit losses	$ 89.0	$ 54.8
PROPERTY AND EQUIPMENT, accumulated depreciation	$ 2,400.0	$ 2,300.0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock authorized (in shares)	1,500,000,000	1,500,000,000
Common stock issued (in shares)	63,562,149	63,562,149
Treasury stock (in shares)	26,686,647	24,527,869