Accounts Receivable - Schedule of Accounts Receivable (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, before allowance for credit loss	$ 1,239.3	$ 1,112.6
Less: Allowance for doubtful accounts	(2.3)	(7.1)
Total accounts receivable, net	1,237.0	1,105.5
Contracts in transit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, before allowance for credit loss	497.4	559.7
Trade receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, before allowance for credit loss	166.5	135.7
Vehicle receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, before allowance for credit loss	243.7	191.4
Manufacturer receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, before allowance for credit loss	306.3	216.5
Other receivables, current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, before allowance for credit loss	$ 25.4	$ 9.3

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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