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Represents the percentage of additional investment ownership interest acquired during the period.

No definition available.

Name:	pag_InvestmentAdditionalOwnershipPercentage
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The percentage of investment ownership.

No definition available.

Name:	pag_InvestmentOwnershipPercentage
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Period Type:	instant

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

No definition available.

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Represents the minimum number of vehicle brands offered.

No definition available.

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

No definition available.

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Represents the minimum number of vehicles retailed and wholesaled.

No definition available.

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Number of franchises acquired.

No definition available.

Name:	pag_NumberOfFranchisesAcquired
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Represents the number of franchises disposed of by the entity during the period.

No definition available.

Name:	pag_NumberOfFranchisesDisposed
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Represents the number of full service retail locations acquired.

No definition available.

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

No definition available.

Name:	pag_NumberOfFullServiceRetailLocationsOperated
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Represents the number of operating franchises.

No definition available.

Name:	pag_NumberOfOperatingFranchises
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Total number of owned and operated franchises.

No definition available.

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Number of owned and operated franchises in domestic country.

No definition available.

Name:	pag_NumberOfOwnedAndOperatedFranchisesInDomesticCountry
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Data Type:	xbrli:integerItemType
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Number of owned and operated franchises in foreign countries.

No definition available.

Name:	pag_NumberOfOwnedAndOperatedFranchisesInForeignCountries
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Data Type:	xbrli:integerItemType
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Represents the number of retail commercial vehicle dealerships owned by the reporting entity.

No definition available.

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

n/a

No definition available.

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Data Type:	xbrli:stringItemType
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- References

No definition available.

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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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13537-108611

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Data Type:	num:percentItemType
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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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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.

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=26872669&loc=d3e20235-122688

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 320

-Section S99

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611443-123010

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Data Type:	num:percentItemType
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Data Type:	na
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Data Type:	na
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Name:	us-gaap_BusinessAcquisitionAxis=pag_GermanAutomotiveDealershipJointVentureMember
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Data Type:	na
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Name:	dei_LegalEntityAxis=us-gaap_PartnershipInterestMember
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