Revenues - Contract Balances (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Contract Balances
Accounts receivable	$ 993.3	$ 1,002.1
Unearned revenues	299.2	266.8
Contracts in transit
Contract Balances
Accounts receivable	255.5	281.7
Vehicle receivables
Contract Balances
Accounts receivable	149.5	136.3
Manufacturer receivables
Contract Balances
Accounts receivable	233.3	233.3
Trade receivables
Contract Balances
Accounts receivable	$ 331.3	$ 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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