Interim Financial Statements - Business Overview (Details) vehicle in Thousands, employee in Thousands, $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023 USD ($) state location dealership vehicle franchise	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) center location brand franchise dealership employee state vehicle	Sep. 30, 2022 USD ($) franchise dealership	Dec. 31, 2022 USD ($)
Interim Financial Statements [Line Items]
Number of PAG employees | employee			28
Number of PTL employees | employee			44
Revenues | $	$ 7,447.8	$ 6,920.7	$ 22,255.3	$ 20,803.0
Minimum number of vehicle brands offered | brand			35
U.S. and Puerto Rico | Retail automotive dealership revenues | Geographic
Interim Financial Statements [Line Items]
Percentage of total			55.00%
Outside the U.S. | Retail automotive dealership revenues | Geographic
Interim Financial Statements [Line Items]
Percentage of total			45.00%
U.S.
Interim Financial Statements [Line Items]
Number of franchises acquired			2
Number of franchises disposed			7
Retail automotive dealership
Interim Financial Statements [Line Items]
Revenues | $	$ 6,325.4	5,757.8	$ 19,031.2	$ 17,784.3	$ 23,700.0
Total number of owned and operated franchises	336		336
Number of franchises acquired				19
Retail automotive dealership | Retail automotive dealership revenues | Premium brands
Interim Financial Statements [Line Items]
Percentage of total			71.00%
Retail automotive dealership | Outside the U.S.
Interim Financial Statements [Line Items]
Number of owned and operated franchises outside US	189		189
Retail automotive dealership | U.S. and U.K.
Interim Financial Statements [Line Items]
Number of stand-alone used vehicle dealerships operated in United States and United Kingdom | dealership	20		20
Retail automotive dealership | U.S.
Interim Financial Statements [Line Items]
Revenues | $	$ 3,595.9	3,400.8	$ 10,511.1	$ 10,188.3
Number of owned and operated franchises in US	147		147
Number of retail locations operated | dealership			7
Number of franchises acquired				4
Number of franchises disposed			6
Retail automotive dealership | U.K.
Interim Financial Statements [Line Items]
Revenues | $	$ 2,306.8	2,002.0	$ 7,180.7	$ 6,461.3
Number of retail locations operated | dealership			13
Number of franchises acquired				15
Number of franchises disposed			2
CarShop Satellite | U.S.
Interim Financial Statements [Line Items]
Number of franchises disposed			1
Retail commercial truck dealership
Interim Financial Statements [Line Items]
Revenues | $	$ 964.7	$ 1,019.5	$ 2,779.5	$ 2,580.5
Number of operating locations | location	44		44
Retail commercial truck dealership | U.S. and Ontario, Canada
Interim Financial Statements [Line Items]
Number of states with dealerships | state	9		9
Retail commercial truck dealership | Canada | Transolutions Truck Centres
Interim Financial Statements [Line Items]
Number of full service dealerships acquired | dealership			3	4
Number of service and parts centers acquired | center			2
Penske Truck Leasing Co L P
Interim Financial Statements [Line Items]
Number of vehicles in fleet | vehicle	442		442
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%
Penske Truck Leasing Co L P
Interim Financial Statements [Line Items]
Penske transportation solutions, ownership percentage	28.90%		28.90%