Revenues - Contract Balances (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Contract Balances
Accounts receivable	$ 1,040.5	$ 1,114.6
Unearned revenues	301.0	280.2
Contracts in transit
Contract Balances
Accounts receivable	281.6	361.9
Vehicle receivables
Contract Balances
Accounts receivable	205.0	170.6
Manufacturer receivables
Contract Balances
Accounts receivable	205.8	218.9
Trade receivables
Contract Balances
Accounts receivable	$ 325.9	$ 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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