Revenues - Contract Balances (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Contract Balances
Accounts receivable	$ 1,084.0	$ 1,070.3
Unearned revenues	298.9	299.3
Contracts in transit
Contract Balances
Accounts receivable	293.9	272.2
Vehicle receivables
Contract Balances
Accounts receivable	149.9	141.5
Manufacturer receivables
Contract Balances
Accounts receivable	260.8	256.4
Trade receivables
Contract Balances
Accounts receivable	$ 357.9	$ 381.6

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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