Interim Financial Statements - Business Overview (Details)	9 Months Ended
Sep. 30, 2025 franchise dealership state location
Penske Truck Leasing Co L P \| Penske Corporation
Interim Financial Statements [Line Items]
Penske transportation solutions, ownership percentage	41.10%
Penske Truck Leasing Co L P \| Mitsui and Co
Interim Financial Statements [Line Items]
Penske transportation solutions, ownership percentage	30.00%
Retail automotive dealership
Interim Financial Statements [Line Items]
Total number of owned and operated franchises	356
Retail automotive dealership \| Outside the U.S.
Interim Financial Statements [Line Items]
Number of owned and operated franchises outside US	209
Retail automotive dealership \| United States, United Kingdom, And Australia
Interim Financial Statements [Line Items]
Number of stand-alone used vehicle dealerships operated in United States and United Kingdom \| dealership	15
Retail automotive dealership \| U.S.
Interim Financial Statements [Line Items]
Number of owned and operated franchises in US	147
Number of retail locations operated \| dealership	6
Number of retail automotive franchises sold	2
Number of retail automotive franchises opened	1
Retail automotive dealership \| U.K.
Interim Financial Statements [Line Items]
Number of retail locations operated \| dealership	8
Number of vehicle dealership sold \| dealership	1
Number of retail automotive franchises opened	3
Retail automotive dealership \| AUSTRALIA
Interim Financial Statements [Line Items]
Number of retail locations operated \| dealership	1
Retail automotive dealership \| ITALY
Interim Financial Statements [Line Items]
Number of franchises acquired	1
Retail commercial truck dealership
Interim Financial Statements [Line Items]
Number of operating locations \| location	45
Retail commercial truck dealership \| U.S. and Ontario, Canada
Interim Financial Statements [Line Items]
Number of states with dealerships \| state	10
Penske Truck Leasing Co L P
Interim Financial Statements [Line Items]
Penske transportation solutions, ownership percentage	28.90%

Interim Financial Statements [Line Items]

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Represents the number of operating franchises.

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Total number of owned and operated franchises.

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Number of owned and operated franchises in domestic country.

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Number of owned and operated franchises in foreign countries.

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Number Of Retail Automotive Franchises Opened

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Number Of Retail Automotive Franchises Sold

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Number Of States With Locations

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- Definition

The number of used vehicle dealerships operated.

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Number Of Used Vehicle Dealerships Sold

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The number of used vehicle dealerships operated in the United States, United Kingdom, and Australia

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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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- Definition

Number of businesses acquired in business combination.

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-Section 50
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