Revenues - Retail Commercial Truck Dealership (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Revenues
Total revenues	$ 5,773.8	$ 5,009.1
Retail Commercial Truck Dealership
Revenues
Total revenues	434.7	491.4
New vehicle \| Retail Commercial Truck Dealership
Revenues
Total revenues	247.5	318.2
Used vehicle \| Retail Commercial Truck Dealership
Revenues
Total revenues	50.9	34.6
Finance and insurance, net \| Retail Commercial Truck Dealership
Revenues
Total revenues	3.1	3.2
Service and parts \| Retail Commercial Truck Dealership
Revenues
Total revenues	124.7	124.3
Other \| Retail Commercial Truck Dealership
Revenues
Total revenues	$ 8.5	$ 11.1

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details