Revenues - Other Disclosures (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Revenues
Total revenues	$ 6,975.4	$ 5,773.8
Commercial vehicle distribution and other
Revenues
Total revenues	$ 153.9	132.2
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	$ 34.8		$ 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	$ 55.1	$ 61.4