Represents the minimum number of vehicle brands offered.

No definition available.

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Represents the minimum number of vehicles retailed and wholesaled.

+ References

No definition available.

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- Definition

Number of franchises acquired.

+ References

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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Represents the number of operating franchises.

+ References

No definition available.

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Total number of owned and operated franchises.

+ References

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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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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No definition available.

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No definition available.

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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	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020 USD ($) item	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) item location	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Interim Financial Statements
Total revenues \| $	$ 5,971.6	$ 5,967.6	$ 14,631.8	$ 17,287.8
PTL
Interim Financial Statements
Ownership interest in Penske Truck Leasing Co (as a percent)			28.90%
Retail Automotive Dealership
Interim Financial Statements
Total revenues \| $					$ 20,600.0
Number of owned and operated franchises in US	145		145
Minimum number of vehicles retailed and wholesaled			371,000
Number of used vehicle supercenters operated in the U.S. and U.K.	16		16
Number of acquired franchises			0
Number of retail locations operated \| location			6
Retail Automotive Dealership \| UK
Interim Financial Statements
Number of franchises disposed			10
Retail Commercial Truck Dealership \| PTG
Interim Financial Statements
Number of operating locations \| location			25
Automotive dealership revenues \| Geographic \| U.S. and Puerto Rico \| Retail Automotive Dealership
Interim Financial Statements
Automotive dealership revenue (as a percent)			57.00%
Automotive dealership revenues \| Geographic \| Outside the U.S. \| Retail Automotive Dealership
Interim Financial Statements
Automotive dealership revenue (as a percent)			43.00%
CarShop \| Retail Automotive Dealership
Interim Financial Statements
Number of retail locations operated \| location			10
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%
Retail Automotive Dealership
Interim Financial Statements
Total revenues \| $	$ 5,258.0	5,155.4	$ 12,828.1	15,442.9
Total number of owned and operated franchises	311		311
Number of owned and operated franchises outside US	166		166
Retail Automotive Dealership \| UK
Interim Financial Statements
Total revenues \| $	$ 2,105.5	1,859.6	$ 4,608.7	5,827.7
Retail Automotive Dealership \| U.S.
Interim Financial Statements
Total revenues \| $	2,780.7	2,995.5	$ 7,288.4	8,624.1
Retail Automotive Dealership \| Automotive dealership revenues \| Premium brands \| Retail Automotive Dealership
Interim Financial Statements
Automotive dealership revenue (as a percent)			70.00%
Minimum number of vehicle brands offered			35
Retail Commercial Truck Dealership
Interim Financial Statements
Total revenues \| $	590.9	692.3	$ 1,481.5	1,451.4
Commercial Vehicle Distribution and Other
Interim Financial Statements
Total revenues \| $	$ 122.7	$ 119.9	$ 322.2	$ 393.5