Revenues - Contract Balances (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Contract Balances
Accounts receivable	$ 1,043.1	$ 1,002.1
Unearned revenues	294.6	266.8
Contracts in transit
Contract Balances
Accounts receivable	262.7	281.7
Vehicle receivables
Contract Balances
Accounts receivable	180.5	136.3
Manufacturer receivables
Contract Balances
Accounts receivable	217.6	233.3
Trade receivables
Contract Balances
Accounts receivable	$ 358.0	$ 326.9

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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