Revenues - Retail Automotive Dealership (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Revenues
Total revenues	$ 27,814.8	$ 25,554.7	$ 20,443.9
U.S.
Revenues
Total revenues	16,801.7	15,275.9	12,105.1
Retail automotive dealership
Revenues
Total revenues	23,694.7	22,513.3	17,928.8
Retail automotive dealership | U.S.
Revenues
Total revenues	13,712.7	13,075.8	10,270.3
Retail automotive dealership | U.K.
Revenues
Total revenues	8,443.4	7,984.1	6,344.1
Retail automotive dealership | Germany, Italy, and Japan
Revenues
Total revenues	1,538.6	1,453.4	1,314.4
New vehicle | Retail automotive dealership
Revenues
Total revenues	10,050.5	9,843.2	8,080.5
Used vehicle | Retail automotive dealership
Revenues
Total revenues	9,011.6	8,549.0	6,414.7
Finance and insurance, net | Retail automotive dealership
Revenues
Total revenues	848.1	780.5	576.3
Service and parts | Retail automotive dealership
Revenues
Total revenues	2,426.7	2,165.6	1,883.7
Fleet and wholesale | Retail automotive dealership
Revenues
Total revenues	$ 1,357.8	$ 1,175.0	$ 973.6