Inventories (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Inventory [Line Items]
Total inventories	$ 2,385.5	$ 2,492.9
New vehicle retail
Inventory [Line Items]
Total inventories	812.9	1,556.6
Used vehicles
Inventory [Line Items]
Total inventories	1,418.3	835.9
Parts and accessories
Inventory [Line Items]
Total inventories	$ 154.3	$ 100.4

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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