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Represents the aggregate amount of reserves for chargeback of sales commission as of the balance sheet date.

No definition available.

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

- References

No definition available.

Name:	pag_SelfInsuranceAbstract
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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 720
-SubTopic 35
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848

Name:	us-gaap_AdvertisingExpense
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Total amount received by an entity from a vendor under a cooperative advertising arrangement that has been offset against advertising expense.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 50
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=68069731&loc=d3e63872-111659

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cooperative Advertising
-URI http://asc.fasb.org/extlink&oid=51574790

Name:	us-gaap_CooperativeAdvertisingAmount
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

Name:	us-gaap_DefinedContributionPensionAndOtherPostretirementPlansDisclosureAbstract
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Data Type:	xbrli:stringItemType
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The amount of the cost recognized during the period for defined contribution plans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

Name:	us-gaap_DefinedContributionPlanCostRecognized
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

This item represents disclosure of all significant concentrations of credit risk or market risk arising from the subject financial instrument (as defined), whether from an individual counterparty or groups of counterparties.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13587-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 958
-SubTopic 320
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=64935638&loc=d3e95693-112898