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Equity Method Investees - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Significant Equity Method Investees
Equity method investments	$ 1,636.9	$ 1,688.1
Equity in earnings of affiliates	$ 494.2	374.5	$ 169.0
The Nix Group
Significant Equity Method Investees
Penske transportation solutions, ownership percentage	50.00%
Barcelona Premium SL
Significant Equity Method Investees
Penske transportation solutions, ownership percentage	50.00%
Penske Commercial Leasing Australia
Significant Equity Method Investees
Penske transportation solutions, ownership percentage	28.00%
PTL
Significant Equity Method Investees
Penske transportation solutions, ownership percentage	28.90%
Equity method investments	$ 1,590.9	$ 1,643.1