Revenues - Other Disclosures (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Revenues
Total revenues	$ 6,920.7	$ 6,497.3	$ 20,803.0	$ 19,258.6
Commercial vehicle distribution and other
Revenues
Total revenues	143.4	145.1	$ 438.2	441.9
Vehicle Sales | Retail Automotive and Retail Commercial Truck Dealership
Revenues
Payment period			30 days
Service and parts | Retail Automotive and Retail Commercial Truck Dealership
Revenues
Payment period			30 days
Finance and insurance, net | Retail Automotive and Retail Commercial Truck Dealership
Revenues
Payment period			30 days
Aggregate reserves relating to chargeback activity	37.2		$ 37.2		$ 33.7
Penske Australia | Commercial vehicle distribution and other
Revenues
Payment period			30 days
Penske Australia | Service and parts | Commercial vehicle distribution and other
Revenues
Total revenues	$ 62.7	$ 69.5	$ 178.3	$ 210.7