No definition available.

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

- Definition

The percentage points to be added to the applicable rate of the ten-year U.S. Treasury to calculate the new distribution rate on the preferred units if the holders elect to reset the distribution rate.

+ References

No definition available.

+ Details

Name:	pagp_PreferredUnitsDistributionRateResetBasisSpreadOnVariableRate
Namespace Prefix:	pagp_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The quarterly distributions per unit to which holders of the preferred units are entitled.

+ References

No definition available.

+ Details

Name:	pagp_PreferredUnitsQuarterlyDistributionsPerUnit
Namespace Prefix:	pagp_
Data Type:	dtr-types1:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents disclosure of the aggregate cash dividends paid to the entity by consolidated subsidiaries.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

+ Details

Name:	us-gaap_CashDividendsPaidToParentCompanyByConsolidatedSubsidiaries
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Per unit of ownership amount of cash distributions paid to unit-holder of a limited partnership (LP).

+ References

+ Details

Name:	us-gaap_DistributionMadeToLimitedPartnerDistributionsPaidPerUnit
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(20))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(24))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
-SubTopic 405
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480191/946-405-45-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(15)(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(15)(5))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

+ Details

Name:	us-gaap_DividendsPayableCurrentAndNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-SubTopic 405
-Topic 942
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481071/942-405-45-2

+ Details

Name:	us-gaap_DividendsPreferredStock
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The total amount of distributions to limited partners.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB TOPIC 4.F)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-5

+ Details

Name:	us-gaap_LimitedPartnersCapitalAccountDistributionAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

+ References

+ Details

Name:	us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Total distributions to each class of partners (i.e., general, limited and preferred partners).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-5

+ Details

Name:	us-gaap_PartnersCapitalAccountDistributions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Aggregate dividends paid during the period for each share of preferred stock outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_PreferredStockDividendsPerShareCashPaid
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_PartnerCapitalComponentsAxis=us-gaap_NoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DistributionsMadeToMemberOrLimitedPartnerByDistributionTypeAxis=us-gaap_CashDistributionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ConsolidatedEntitiesAxis=pagp_ConsolidatedJointVentureEntitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=pagp_PlainsAAPLPMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=srt_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=pagp_PlainsOryxPermianBasinLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=pagp_CactusIIPipelineLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=pagp_RedRiverPipelineCompanyLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LimitedPartnersCapitalAccountByClassAxis=pagp_SeriesBPreferredUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=pagp_PlainsAllAmericanPipelineLPMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_OtherCurrentLiabilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LimitedPartnersCapitalAccountByClassAxis=pagp_SeriesAPreferredUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LimitedPartnersCapitalAccountByClassAxis=pagp_CommonUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=pagp_PublicUnitHoldersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=pagp_PlainsAAPLPMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=pagp_PlainsAllAmericanPipelineLPMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LimitedPartnersCapitalAccountByClassAxis=pagp_CommonUnitsAndSeriesAPreferredUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=pagp_PlainsAAPLPMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=pagp_PlainsOryxPermianBasinLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=pagp_CactusIIPipelineLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=pagp_RedRiverPipelineCompanyLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Partners' Capital and Distributions - Subsidiary Distributions (Details) - USD ($) $ / shares in Units, $ in Millions							3 Months Ended		6 Months Ended
	Aug. 15, 2023	Aug. 14, 2023	May 15, 2023	Feb. 15, 2023	Feb. 14, 2023	Jan. 31, 2023	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Partners' Capital and Distributions
Total distributions paid							$ 322	$ 264	$ 646	$ 500
Noncontrolling Interests
Partners' Capital and Distributions
Total distributions paid							270	222	542	423
Cash Distribution \| Noncontrolling Interests \| Consolidated Joint Venture Entities
Partners' Capital and Distributions
Total distributions paid							73	62	151	121
AAP \| Cash Distribution
Partners' Capital and Distributions
Distributions to noncontrolling interests			$ 13		$ 13
Distributions to PAGP			52		52
Distributions paid to limited partners			$ 65		$ 65
AAP \| Cash Distribution \| Forecast
Partners' Capital and Distributions
Distributions to noncontrolling interests		$ 12
Distributions to PAGP		52
Distributions paid to limited partners		$ 64
Permian JV \| Cash Distribution \| Noncontrolling Interests
Partners' Capital and Distributions
Total distributions paid							53	58	111	112
Cactus II \| Cash Distribution \| Noncontrolling Interests
Partners' Capital and Distributions
Total distributions paid							15		29
Red River \| Cash Distribution \| Noncontrolling Interests
Partners' Capital and Distributions
Total distributions paid							5	$ 4	11	$ 9
Series B Preferred Units \| PAA \| Other current liabilities
Partners' Capital and Distributions
Amount accrued to distributions payable							$ 10		$ 10
Series B Preferred Units \| PAA \| Cash Distribution
Partners' Capital and Distributions
Preferred unit distribution amount (usd per unit)			$ 22.18	$ 22.27
Preferred unit distribution amount			$ 18	$ 18
Series B Preferred Units \| PAA \| Cash Distribution \| Forecast
Partners' Capital and Distributions
Preferred unit distribution amount (usd per unit)	$ 24.10
Preferred unit distribution amount	$ 19
Series A Preferred Units \| PAA
Partners' Capital and Distributions
Distribution rate reset, basis spread on variable rate						5.85%
Quarterly distributions per unit (usd per unit)						$ 0.615
Series A Preferred Units \| PAA \| Cash Distribution
Partners' Capital and Distributions
Preferred unit distribution amount (usd per unit)			$ 0.585		$ 0.525
Preferred unit distribution amount			$ 42		$ 37
Series A Preferred Units \| PAA \| Cash Distribution \| Forecast
Partners' Capital and Distributions
Preferred unit distribution amount (usd per unit)		$ 0.615
Preferred unit distribution amount		$ 44
Common Units \| PAA \| Cash Distribution
Partners' Capital and Distributions
Total distributions paid			$ 187		$ 187
Distributions per common unit, paid (usd per unit)			$ 0.2675		$ 0.2675
Common Units \| PAA \| Cash Distribution \| Public
Partners' Capital and Distributions
Total distributions paid			$ 122		$ 122
Common Units \| PAA \| Cash Distribution \| AAP
Partners' Capital and Distributions
Total distributions paid			$ 65		$ 65
Common Units \| PAA \| Cash Distribution \| Forecast
Partners' Capital and Distributions
Total distributions paid		$ 187
Distributions per common unit, paid (usd per unit)		$ 0.2675
Common Units \| PAA \| Cash Distribution \| Forecast \| Public
Partners' Capital and Distributions
Total distributions paid		$ 123
Common Units \| PAA \| Cash Distribution \| Forecast \| AAP
Partners' Capital and Distributions
Total distributions paid		$ 64
PAA \| Common Units and Series A Preferred Units
Partners' Capital and Distributions
Noncontrolling interests in subsidiaries (percent)							69.00%		69.00%
PAA \| Series B Preferred Units
Partners' Capital and Distributions
Noncontrolling interests in subsidiaries (percent)							100.00%		100.00%
AAP
Partners' Capital and Distributions
Noncontrolling interests in subsidiaries (percent)							19.00%		19.00%
Permian JV
Partners' Capital and Distributions
Noncontrolling interests in subsidiaries (percent)							35.00%		35.00%
Cactus II
Partners' Capital and Distributions
Noncontrolling interests in subsidiaries (percent)							30.00%		30.00%
Red River
Partners' Capital and Distributions
Noncontrolling interests in subsidiaries (percent)							33.00%		33.00%