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

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

- 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:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DistributionMadeToLimitedPartnerLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

- Details

Name:	us-gaap_LimitedPartnersCapitalAccountByClassAxis=paa_CommonUnitsMember
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_CounterpartyNameAxis=paa_PublicUnitHoldersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

- Details

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

Partners' Capital and Distributions - Common Unit Distributions (Details) - Common Units - 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
Distribution Made to Limited Partner [Line Items]
Distributions per common unit (in dollars per unit)			$ 0.18	$ 0.18	$ 0.18	$ 0.36	$ 0.36	$ 0.36	$ 0.36	$ 0.30	$ 0.90	$ 1.38
Cash Distribution
Distribution Made to Limited Partner [Line Items]
Distributions paid to limited partners											$ 655	$ 1,004	$ 871
Distributions per common unit (in dollars per unit)											$ 0.90	$ 1.38	$ 1.20
Public \| Cash Distribution
Distribution Made to Limited Partner [Line Items]
Distributions paid to limited partners											$ 432	$ 632	$ 532
AAP \| Cash Distribution
Distribution Made to Limited Partner [Line Items]
Distributions paid to limited partners											$ 223	$ 372	$ 339
Fourth quarter distribution \| Subsequent Event \| Cash Distribution
Distribution Made to Limited Partner [Line Items]
Distributions paid to limited partners	$ 130
Distribution per common unit declared (in dollars per unit)		$ 0.18
Fourth quarter distribution \| Subsequent Event \| AAP \| Cash Distribution
Distribution Made to Limited Partner [Line Items]
Distributions paid to limited partners	$ 44