XML 101 R78.htm IDEA: XBRL DOCUMENT v3.20.4

Partners' Capital and Distributions - Distributions, Class A (Details) - Class A Shares - USD ($) $ / shares in Units, $ in Millions			3 Months Ended								12 Months Ended
	Feb. 12, 2021	Jan. 07, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Partners Capital and Distribution [Line Items]
Percentage of available cash distributed											100.00%
Number of days after end of quarter within which distributions must be paid to shareholders											55 days
Cash distributions per Class A share (in dollars per share)			$ 0.18	$ 0.18	$ 0.18	$ 0.36	$ 0.36	$ 0.36	$ 0.36	$ 0.30	$ 0.90	$ 1.38
Cash Distribution
Partners Capital and Distribution [Line Items]
Distributions paid to limited partners											$ 166	$ 231	$ 189
Cash distributions per Class A share (in dollars per share)											$ 0.90	$ 1.38	$ 1.20
Fourth quarter distribution | Cash Distribution | Subsequent Event
Partners Capital and Distribution [Line Items]
Distributions paid to limited partners	$ 35
Distributions per Class A share declared (in dollars per share)		$ 0.18

X

- Definition

The number of days after the end of the relevant quarter within which distributions of available cash must be paid to shareholders.

+ References

No definition available.

+ Details

Name:	pagp_NumberOfDaysRequiredForDistributionToShareholdersAfterEndOfQuarter
Namespace Prefix:	pagp_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

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

X

- Definition

This element represents the percentage of cash distributed out of available cash.

+ References

No definition available.

+ Details

Name:	pagp_PercentageDistributionOfAvailableCash
Namespace Prefix:	pagp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

+ Details

Name:	us-gaap_DistributionMadeToLimitedPartnerDistributionsDeclaredPerUnit
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

X

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

+ Details

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

X

- Definition

The total amount of distributions to limited partners.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB TOPIC 4.F)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187171-122770

+ Details

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

X

- Details

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

X

- Details

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

X

- Details

Name:	us-gaap_DividendsAxis=pagp_FourthQuarterDistributionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: