Revenues - Other Disclosures (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues
Total revenues	$ 25,554.7	$ 20,443.9	$ 23,179.4
Commercial vehicle distribution
Revenues
Total revenues	$ 575.7	454.2	$ 513.1
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	$ 33.7	28.7
Penske Australia | Commercial vehicle distribution
Revenues
Payment period	30 days
Penske Australia | Service and parts | Commercial vehicle distribution
Revenues
Total revenues	$ 242.8	$ 220.3