Revenues - Commercial Vehicle Distribution and Other (Details) - Commercial Vehicle Distribution and Other - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues
Total revenues	$ 158.5
Penske Commercial Vehicles Australia
Revenues
Total revenues	57.5
Penske Power Systems
Revenues
Total revenues	100.2
Other
Revenues
Total revenues	$ 0.8
Without Adoption of ASC 606
Revenues
Total revenues		$ 113.0
Without Adoption of ASC 606 | Penske Commercial Vehicles Australia
Revenues
Total revenues		64.8
Without Adoption of ASC 606 | Penske Power Systems
Revenues
Total revenues		47.3
Without Adoption of ASC 606 | Other
Revenues
Total revenues		$ 0.9