Revenues - Contract Balances (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Contract Balances
Accounts receivable	$ 831.3	$ 734.0
Unearned revenues	267.4	297.0
Unearned revenue recognized as revenue	178.1
Contracts in transit
Contract Balances
Accounts receivable	255.0	198.7
Vehicle receivables
Contract Balances
Accounts receivable	211.9	197.7
Manufacturer receivables
Contract Balances
Accounts receivable	157.8	157.7
Trade receivables
Contract Balances
Accounts receivable	$ 184.7	$ 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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