Revenues - Contract Balances (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Contract Balances
Accounts receivable	$ 906.7	$ 734.0
Unearned revenues	291.7	297.0
Revenue recognized from unearned revenue	217.7
Contracts in transit
Contract Balances
Accounts receivable	281.7	198.7
Vehicle receivables
Contract Balances
Accounts receivable	235.1	197.7
Manufacturer receivables
Contract Balances
Accounts receivable	178.9	157.7
Trade receivables
Contract Balances
Accounts receivable	$ 191.1	$ 164.5

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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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