Revenues - Contract Balances (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Dec. 31, 2022
Contract Balances
Accounts receivable	$ 920.2	$ 906.7
Unearned revenues	280.6	291.7
Unearned revenue recognized as revenue	118.7
Contracts in transit
Contract Balances
Accounts receivable	246.9	281.7
Vehicle receivables
Contract Balances
Accounts receivable	263.6	235.1
Manufacturer receivables
Contract Balances
Accounts receivable	193.3	178.9
Trade receivables
Contract Balances
Accounts receivable	$ 198.7	$ 191.1

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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