Increase In Dealership Locations, Percent

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- Definition

Investment Ownership Percentage Acquired

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- Definition

Number Of Collision Centers Added

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- Definition

Number Of Dealerships Opened

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No definition available.

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- Definition

Number Of Franchises Acquired

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- Definition

Number Of Franchises Awarded To Reporting Entity

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- Definition

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

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No definition available.

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- Definition

Number Of Full Service Dealerships Added

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No definition available.

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- Definition

Represents the number of operating franchises.

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No definition available.

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- Definition

Total number of owned and operated franchises.

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No definition available.

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- Definition

Number of owned and operated franchises in domestic country.

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No definition available.

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- Definition

Number of owned and operated franchises in foreign countries.

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- Definition

Number Of Parts And Service Centers Added

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No definition available.

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- Definition

The number of retail locations operated.

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No definition available.

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- Definition

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

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Number Of Vehicles In Fleet

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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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The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

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Organization and Summary of Significant Accounting Policies - Business Overview (Details) vehicle in Thousands, $ in Millions	1 Months Ended		12 Months Ended
	Oct. 31, 2021	Apr. 30, 2021 dealership	Dec. 31, 2021 USD ($) franchise location dealership vehicle	Dec. 31, 2020 USD ($)
Significant Accounting Policies
Accounts receivable \| $			$ 734.0	$ 806.9
PTL
Significant Accounting Policies
Ownership interest in Penske Truck Leasing Co (as a percent)			28.90%
Number of vehicles in fleet \| vehicle			360
Penske Corporation \| PTL
Significant Accounting Policies
Ownership interest in Penske Truck Leasing Co (as a percent)			41.10%
Mitsui and Co \| PTL
Significant Accounting Policies
Ownership interest in Penske Truck Leasing Co (as a percent)			30.00%
Retail automotive dealership \| Manufacturer receivables
Significant Accounting Policies
Accounts receivable \| $			$ 157.7	$ 193.6
Retail automotive dealership \| U.S.
Significant Accounting Policies
Number of franchises acquired \| franchise			3
Number of franchises awarded to reporting entity \| franchise			1
Retail automotive dealership \| U.K.
Significant Accounting Policies
Number of franchises awarded to reporting entity \| franchise			1
Number of franchises disposed \| franchise			1
Retail automotive dealership \| Retail Automotive Dealership
Significant Accounting Policies
Number of owned and operated franchises \| franchise			320
Number of owned and operated franchises in US \| franchise			146
Number of owned and operated franchises outside US \| franchise			174
Number of used vehicle supercenters operated in the U.S. and U.K.			23
Retail automotive dealership \| Retail Automotive Dealership \| Nicole Group
Significant Accounting Policies
Ownership percentage acquired	51.00%
Retail automotive dealership \| Retail Automotive Dealership \| CarShop
Significant Accounting Policies
Increase in number of dealership locations, percent			35.00%
Retail automotive dealership \| Retail Automotive Dealership \| CarShop \| U.S.
Significant Accounting Policies
Number of retail locations operated			8
Number of dealerships opened			2
Retail automotive dealership \| Retail Automotive Dealership \| CarShop \| U.K.
Significant Accounting Policies
Number of retail locations operated			15
Number of dealerships opened			4
Retail automotive dealership \| Audi/Volkswagen/Porsche/Bentley \| Automotive dealership revenues \| Customer Concentration Risk
Significant Accounting Policies
Percentage of total			22.00%
Retail automotive dealership \| BMW, MINI \| Automotive dealership revenues \| Customer Concentration Risk
Significant Accounting Policies
Percentage of total			24.00%
Retail automotive dealership \| Toyota/Lexus \| Automotive dealership revenues \| Customer Concentration Risk
Significant Accounting Policies
Percentage of total			14.00%
Retail commercial truck dealership \| Retail Commercial Truck Dealership \| PTG
Significant Accounting Policies
Number of operating locations \| location			37
Retail commercial truck dealership \| Retail Commercial Truck Dealership \| PTG \| Kansas City Freightliner
Significant Accounting Policies
Number of full service dealerships added		4	4
Number of parts and service centers added		4	4
Number of collision centers added		2	2
Retail commercial truck dealership \| Retail Commercial Truck Dealership \| PTG \| McCoy Freightliner
Significant Accounting Policies
Number of full service dealerships added		2	2