Name:	pagp_AllocatedShareBasedCompensationBenefit
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Aggregate cash payments made towards distribution equivalent rights during the reporting period that have been earned by satisfying service and performance requirements.

No definition available.

Name:	pagp_DistributionEquivalentRightsCashPayments
Namespace Prefix:	pagp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

Name:	pagp_OtherConsolidatedEquityCompensationInformationAbstract
Namespace Prefix:	pagp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The total settlement date fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units in accordance with the terms of the arrangement, and for which no expense was recognized in equity during prior periods.

No definition available.

Name:	pagp_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalSettlementFairValue
Namespace Prefix:	pagp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements that vested during the reporting period by satisfying service and performance requirements.

No definition available.

Name:	pagp_ShareBasedCompensationArrangementByShareBasedPaymentAwardVestedInPeriodCashSettled
Namespace Prefix:	pagp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F