Equity Method Investees - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Equity Method Investees
Equity method investments	$ 1,827.0	$ 1,774.9
Equity in earnings of affiliates	200.7	293.7	$ 494.2
Equity method investment, distribution	99.1	169.9	356.6
Retained earnings, undistributed earnings from equity method investees	$ 927.5
Barcelona Premium SL
Equity Method Investees
Ownership percentage	50.00%
Penske Commercial Leasing Australia \| Corporate Joint Venture
Equity Method Investees
Ownership percentage	28.00%
Penske Truck Leasing Co LP
Equity Method Investees
Equity method investments	$ 1,803.9	1,725.1
Penske Truck Leasing Co LP \| Corporate Joint Venture
Equity Method Investees
Ownership percentage	28.90%
Pro rata quarterly distributions, percentage of net income	50.00%
Debt-to-equity ratio	3.0
Distribution threshold, percentage of net income	0.80
Equity method investment, distribution	$ 98.4	$ 168.8	$ 356.6

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Equity Method Investment, Distribution Threshold, Percentage Of Net Income

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Equity Method Investment, Distribution Threshold When Debt-To-Equity Ratio is Less Than 3.0 to 1.0, Percentage Of Net Income

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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Amount of consolidated retained earnings that represent undistributed (not yet received) earnings from 50 percent or less owned persons accounted for by the equity method (equity method investees).

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