The percentage of investment ownership.

No definition available.

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Period Type:	instant

- Definition

Represents the ownership interest acquired by the entity during the period.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Represents the minimum number of dealership locations wherein the vehicles were distributed and sold.

+ References

No definition available.

+ Details

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Namespace Prefix:	pag_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of dealerships operated.

+ References

No definition available.

+ Details

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Namespace Prefix:	pag_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of franchises acquired.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

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

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Represents the number of full service retail locations operated by the equity method investee.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Total number of owned and operated franchises.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Number of owned and operated franchises in domestic country.

+ References

No definition available.

+ Details

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Namespace Prefix:	pag_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of owned and operated franchises in foreign countries.

+ References

No definition available.

+ Details

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Namespace Prefix:	pag_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the number of retail locations acquired.

+ References

No definition available.

+ Details

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Namespace Prefix:	pag_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of truck retail dealerships owned by the reporting entity.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Represents the total amount of receivables from manufacturers as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	pag_
Data Type:	xbrli:monetaryItemType
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- References

No definition available.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the aggregate cost of investments accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of units or percentage investment held by one or more members or limited partners of the LLC or LP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

Name:	us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=pag_PremierTruckGroupMember
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- Details

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- Details

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Name:	dei_LegalEntityAxis=pag_GECapitalMember
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Data Type:	na
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- Details

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- Details

Name:	us-gaap_BusinessAcquisitionAxis=pag_SpecificDealerGroupInUkMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FranchisorDisclosureAxis=pag_RetailCommercialTruckDealershipOperationsMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_FranchisorDisclosureAxis=pag_CommercialVehicleDistributionOperationsMember
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Data Type:	na
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- Details

Name:	us-gaap_FranchisorDisclosureAxis=pag_BmwMiniMember
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Organization and Summary of Significant Accounting Policies - Business Overview (Details) $ in Millions			1 Months Ended					3 Months Ended								12 Months Ended
	Jul. 27, 2016 USD ($)	Jul. 26, 2016	Dec. 31, 2016 USD ($) item	Oct. 31, 2016 item	Jul. 31, 2016 item	Apr. 30, 2016 item	Feb. 28, 2015 item	Dec. 31, 2016 USD ($) item	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) item	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Jan. 31, 2016	Aug. 31, 2015	Oct. 31, 2014
Significant Accounting Policies
Total revenues \| $								$ 4,887.8	$ 5,152.0	$ 5,254.1	$ 4,824.6	$ 4,921.3	$ 4,960.1	$ 4,920.6	$ 4,482.9	$ 20,118.5	$ 19,284.9	$ 17,232.0
Receivables from manufacturers \| $			$ 196.5					$ 196.5				$ 178.9				$ 196.5	$ 178.9
German Automotive Dealership Group
Significant Accounting Policies
Ownership interest (as a percent)			68.00%					68.00%					60.00%			68.00%				50.00%
Ownership acquired (as a percent)											8.00%						10.00%
Nicole Group
Significant Accounting Policies
Ownership percentage of equity method investment			49.00%					49.00%								49.00%			49.00%
PTG
Significant Accounting Policies
Ownership interest (as a percent)			100.00%					100.00%								100.00%
PTL
Significant Accounting Policies
Ownership interest in Penske Truck Leasing Co (as a percent)		9.00%														23.40%
Ownership acquired (as a percent)	14.40%
Cost of acquisition \| $	$ 498.5
Ownership percentage of equity method investment			23.40%					23.40%								23.40%
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)																20.00%
GEC \| PTL
Significant Accounting Policies
Ownership interest in Penske Truck Leasing Co (as a percent)																15.50%
Retail Automotive Dealership
Significant Accounting Policies
Total number of owned and operated franchises			355					355								355
Number of owned and operated franchises in US			164					164								164
Number of owned and operated franchises outside US			191					191								191
Number of acquired franchises																20
Number of franchises awarded to the reporting entity																7
Number of franchises disposed																10
Retail Automotive Dealership \| Northern Italy
Significant Accounting Policies
Number of acquired franchises				7
Ownership interest (as a percent)				84.00%
Retail Automotive Dealership \| Nicole Group
Significant Accounting Policies
Ownership percentage of equity method investment																			49.00%
Retail Automotive Dealership \| Dealer Group in UK
Significant Accounting Policies
Number of acquired franchises					12
Retail Commercial Truck Dealership \| PTG
Significant Accounting Policies
Number of dealerships operated																20
Ownership interest (as a percent)			100.00%					100.00%				96.00%				100.00%	96.00%
Ownership acquired (as a percent)																	5.00%
Number of full service retail locations operated			14					14								14
Number of retail locations acquired			2			4	2
Ownership percentage of equity method investment																					32.00%
Commercial Vehicle Distribution
Significant Accounting Policies
Minimum number of dealership locations																70
Number of retail dealerships owned by the reporting entity																6
BMW, MINI \| Automotive dealership revenues
Significant Accounting Policies
Percentage of total																25.00%
Audi/Volkswagen/Porsche/Bentley \| Automotive dealership revenues
Significant Accounting Policies
Percentage of total																24.00%
Mercedes-Benz/Sprinter/smart \| Automotive dealership revenues
Significant Accounting Policies
Percentage of total																10.00%
Toyota/Lexus \| Automotive dealership revenues
Significant Accounting Policies
Percentage of total																15.00%
Retail Automotive Dealership
Significant Accounting Policies
Total revenues \| $																$ 18,673.2	$ 17,896.3	16,657.5
Retail Commercial Truck Dealership
Significant Accounting Policies
Total revenues \| $																1,000.7	944.1	125.6
Commercial Vehicle Distribution and Other
Significant Accounting Policies
Total revenues \| $																$ 444.6	$ 444.5	$ 448.9
Volkswagen Dealership \| Retail Automotive Dealership \| Dealer Group in UK
Significant Accounting Policies
Number of acquired franchises					7
BMW Dealership \| Nicole Group
Significant Accounting Policies
Number of dealerships operated																4
BMW Dealership \| Retail Automotive Dealership \| Dealer Group in UK
Significant Accounting Policies
Number of acquired franchises					1
MINI Dealership \| Nicole Group
Significant Accounting Policies
Number of dealerships operated																2
MINI Dealership \| Retail Automotive Dealership \| Dealer Group in UK
Significant Accounting Policies
Number of acquired franchises					1
Audi Dealership \| Retail Automotive Dealership \| Northern Italy
Significant Accounting Policies
Number of acquired franchises				1
Audi Dealership \| Retail Automotive Dealership \| Dealer Group in UK
Significant Accounting Policies
Number of acquired franchises					1
Skoda Dealership \| Retail Automotive Dealership \| Dealer Group in UK
Significant Accounting Policies
Number of acquired franchises					1
SEAT Dealership \| Retail Automotive Dealership \| Dealer Group in UK
Significant Accounting Policies
Number of acquired franchises					1
Porsche Dealership \| Retail Automotive Dealership \| Northern Italy
Significant Accounting Policies
Number of acquired franchises				3
Land Rover Dealership \| Retail Automotive Dealership \| Northern Italy
Significant Accounting Policies
Number of acquired franchises				1
Volvo Dealership \| Retail Automotive Dealership \| Northern Italy
Significant Accounting Policies
Number of acquired franchises				1
Nissan Dealership \| Retail Automotive Dealership \| Northern Italy
Significant Accounting Policies
Number of acquired franchises				1
Scion \| Retail Automotive Dealership
Significant Accounting Policies
Number of franchises disposed																17
ALPINA Dealership \| Nicole Group
Significant Accounting Policies
Number of dealerships operated																2