Revenues - Contract Balances (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Contract Balances
Accounts receivable	$ 734.0	$ 806.9
Unearned revenues	297.0	262.9
Revenue recognized from unearned revenue	174.3
Contracts in transit
Contract Balances
Accounts receivable	198.7	254.0
Vehicle receivables
Contract Balances
Accounts receivable	197.7	216.2
Trade receivables
Contract Balances
Accounts receivable	$ 164.5	$ 135.3

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