Represents the minimum number of vehicle brands offered.

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Represents the minimum number of vehicles retailed and wholesaled.

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No definition available.

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Number of collision centers added.

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No definition available.

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Number of brands represented by franchises awarded to the reporting entity.

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No definition available.

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Represents the number of franchises disposed of by the entity during the period.

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No definition available.

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Number of full service dealerships added to existing operations.

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No definition available.

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Represents the number of operating franchises.

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No definition available.

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Total number of owned and operated franchises.

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No definition available.

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Number of owned and operated franchises in domestic country.

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No definition available.

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Number of owned and operated franchises in foreign countries.

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Number of parts and service centers added.

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No definition available.

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The number of retail locations operated.

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No definition available.

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The number of stand-alone used vehicle supercenters operated in the United States and United Kingdom.

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The number uf used vehicle supercenters operated in the United Kingdom.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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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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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Interim Financial Statements - Business Overview (Details) $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 29, 2021 item	Mar. 31, 2021 USD ($) location item	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Interim Financial Statements
Total revenues \| $		$ 5,773.8	$ 5,009.1
PTL
Interim Financial Statements
Ownership interest in Penske Truck Leasing Co (as a percent)		28.90%
Retail Automotive Dealership
Interim Financial Statements
Total number of owned and operated franchises		304
Number of owned and operated franchises in US		143
Number of owned and operated franchises outside US		161
Minimum number of vehicles retailed and wholesaled		135,000
Minimum number of vehicle brands offered		35
Number of used vehicle supercenters operated in the U.S. and U.K.		17
Number uf used vehicle supercenters operated in the U.K.		11
Retail Commercial Truck Dealership \| KCFL
Interim Financial Statements
Number of full service dealerships added	4
Number of parts and service centers added	4
Number of collision centers added	2
UK \| Retail Automotive Dealership
Interim Financial Statements
Number of franchises disposed		1
Revenues \| Geographic \| U.S. and Puerto Rico
Interim Financial Statements
Automotive dealership revenue (as a percent)		58.00%
Revenues \| Geographic \| Outside the U.S.
Interim Financial Statements
Automotive dealership revenue (as a percent)		42.00%
CarSense \| Retail Automotive Dealership
Interim Financial Statements
Number of retail locations operated \| location		6
CarShop \| Retail Automotive Dealership
Interim Financial Statements
Number of retail locations operated \| location		11
Penske Corporation \| PTL
Interim Financial Statements
Ownership interest in Penske Truck Leasing Co (as a percent)		41.10%
Mitsui and Co \| PTL
Interim Financial Statements
Ownership interest in Penske Truck Leasing Co (as a percent)		30.00%
PTG \| Retail Commercial Truck Dealership
Interim Financial Statements
Number of operating locations \| location		25
Retail Automotive Dealership
Interim Financial Statements
Total revenues \| $		$ 5,206.9	4,416.6	$ 17,900.0
Retail Automotive Dealership \| UK
Interim Financial Statements
Total revenues \| $		1,853.4	1,665.4
Retail Automotive Dealership \| U.S.
Interim Financial Statements
Total revenues \| $		$ 3,004.8	2,453.9
Number of franchises awarded to the reporting entity		1
Retail Automotive Dealership \| Revenues \| Premium brands
Interim Financial Statements
Automotive dealership revenue (as a percent)		73.00%
Retail Commercial Truck Dealership
Interim Financial Statements
Total revenues \| $		$ 434.7	491.4
Commercial Vehicle Distribution and Other
Interim Financial Statements
Total revenues \| $		$ 132.2	$ 101.1