Revenues - Contract Balances (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Contract Balances
Accounts receivable	$ 1,002.1	$ 1,114.6
Unearned revenues	266.8	280.2
Contracts in transit
Contract Balances
Accounts receivable	281.7	361.9
Vehicle receivables
Contract Balances
Accounts receivable	136.3	170.6
Manufacturer receivables
Contract Balances
Accounts receivable	233.3	218.9
Trade receivables
Contract Balances
Accounts receivable	$ 326.9	$ 344.1

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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