Organization and Summary of Significant Accounting Policies - Business Overview (Details) $ in Millions	1 Months Ended	12 Months Ended
	Feb. 28, 2022 dealership	Dec. 31, 2022 USD ($) franchise vehicle employee brand state dealership location	Dec. 31, 2021 USD ($) franchise	Dec. 31, 2020 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of PAG employees | employee		26,500
Number of PTL employees | employee		41,500
Revenues | $		$ 27,814.8	$ 25,554.7	$ 20,443.9
Number of vehicle brands | brand		35
Accounts receivable | $		$ 906.7	734.0
Manufacturer receivables
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable | $		$ 178.9	157.7
PTL
Summary Of Significant Accounting Policies [Line Items]
Penske transportation solutions, ownership percentage		28.90%
U.S.
Summary Of Significant Accounting Policies [Line Items]
Revenues | $		$ 16,801.7	15,275.9	12,105.1
U.K.
Summary Of Significant Accounting Policies [Line Items]
Number of franchises disposed		4
Retail automotive dealership revenues | U.S. and Puerto Rico | Geographic
Summary Of Significant Accounting Policies [Line Items]
Percentage of total		58.00%
Retail automotive dealership revenues | Outside the U.S. | Geographic
Summary Of Significant Accounting Policies [Line Items]
Percentage of total		42.00%
Retail automotive dealership
Summary Of Significant Accounting Policies [Line Items]
Revenues | $		$ 23,694.7	22,513.3	17,928.8
Number of owned and operated franchises		338
Retail automotive dealership | Outside the U.S.
Summary Of Significant Accounting Policies [Line Items]
Number of owned and operated franchises outside US		187
Retail automotive dealership | U.S. and U.K.
Summary Of Significant Accounting Policies [Line Items]
Number of used vehicle supercenters operated in the U.S. and U.K. | dealership		21
Number of franchises acquired		19
Retail automotive dealership | U.S.
Summary Of Significant Accounting Policies [Line Items]
Revenues | $		$ 13,712.7	$ 13,075.8	10,270.3
Number of owned and operated franchises in US		151
Number of retail locations operated | dealership		8
Number of franchises acquired		4	3
Number of franchises awarded to reporting entity		2
Number of franchises sold		1
Retail automotive dealership | U.K.
Summary Of Significant Accounting Policies [Line Items]
Revenues | $		$ 8,443.4	$ 7,984.1	6,344.1
Number of retail locations operated | dealership		13
Number of franchises acquired		15
Number of franchises disposed		2
Retail automotive dealership | Retail automotive dealership revenues | Premium Brands
Summary Of Significant Accounting Policies [Line Items]
Percentage of total		71.00%
Retail automotive dealership | Audi/Volkswagen/Porsche/Bentley | Retail automotive dealership revenues | Customer
Summary Of Significant Accounting Policies [Line Items]
Percentage of total		21.00%
Retail automotive dealership | BMW, MINI | Retail automotive dealership revenues | Customer
Summary Of Significant Accounting Policies [Line Items]
Percentage of total		26.00%
Retail automotive dealership | Toyota/Lexus | Retail automotive dealership revenues | Customer
Summary Of Significant Accounting Policies [Line Items]
Percentage of total		14.00%
Retail commercial truck dealership
Summary Of Significant Accounting Policies [Line Items]
Revenues | $		$ 3,541.3	$ 2,465.7	$ 2,060.9
Number of operating locations | location		39
Retail commercial truck dealership | TEAM Truck Centres
Summary Of Significant Accounting Policies [Line Items]
Number of full service dealerships acquired | dealership	4
Retail commercial truck dealership | U.S. and Ontario, Canada
Summary Of Significant Accounting Policies [Line Items]
Number of states with locations | state		9
CarShop Satellite | U.K.
Summary Of Significant Accounting Policies [Line Items]
Number of franchises disposed		2
PTL
Summary Of Significant Accounting Policies [Line Items]
Number of vehicles in fleet | vehicle		414,500
PTL | Penske Corporation
Summary Of Significant Accounting Policies [Line Items]
Ownership interest in Penske Truck Leasing Company		41.10%
PTL | Mitsui and Co
Summary Of Significant Accounting Policies [Line Items]
Ownership interest in Penske Truck Leasing Company		30.00%