Partners' Capital and Distributions - Subsidiary Equity Offerings (Details) $ / shares in Units, shares in Millions, $ in Millions		9 Months Ended
Jan. 28, 2016 $ / shares shares	Sep. 30, 2016 USD ($) item $ / shares shares
Series A Preferred Units \| PAA
Partners Capital and Distributions
Sale of preferred units (units) \| shares	61.0
Cash purchase price (usd per unit)	$ 26.25
Quarterly distribution rate (usd per unit)		$ 0.525
Annualized distribution rate (usd per unit)		$ 2.10
Number of years following issuance after which unitholders have the option to convert units		2 years
Preferred unit conversion ratio		1
Number of years following issuance after which PAA has the option to convert units		3 years
Series A Preferred Units \| PAA \| Preferred Distribution Rate Reset Option
Partners Capital and Distributions
Period after fifth and subsequent anniversaries of issuance for distribution rate reset election option		30 days
Number of distribution rate reset elections allowed \| item		1
Basis spread on variable rate		5.85%
PAA
Partners Capital and Distributions
Noncontrolling interests in subsidiaries (percent)		98.00%
SLC Pipeline LLC
Partners Capital and Distributions
Noncontrolling interests in subsidiaries (percent)		25.00%
AAP
Partners Capital and Distributions
Noncontrolling interests in subsidiaries (percent)		58.00%
Continuous Offering Program \| PAA
Partners Capital and Distributions
Sale of common units (units) \| shares		9.9
Sale of common units, net proceeds \| $		$ 283
Commissions paid to sales agents \| $		$ 2

Represents the costs incurred for commissions paid to the agent under the equity distribution agreement.

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- Definition

Price per unit of partnership interest sold during the period.

+ References

No definition available.

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- References

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- Definition

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

+ References

No definition available.

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- Definition

Ratio applied to the conversion of preferred units into common units.

+ References

No definition available.

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- 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.

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- Definition

The number of times the holders of the preferred units may elect to reset the preferred unit distribution rate.

+ References

No definition available.

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- Definition

Period following the fifth and each subsequent anniversary of the issuance date of the preferred units, within which the holders of the preferred units may elect to reset the preferred unit distribution rate.

+ References

No definition available.

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- Definition

Period following the issuance of the preferred units, after which the entity has the option under certain circumstances to convert the preferred units into common units.

+ References

No definition available.

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- Definition

Period following the issuance of the preferred units, after which the unitholders have the option to convert the preferred units into common units.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Total change in each class of partners' capital accounts during the year due to the sale of units. All partners include general, limited and preferred partners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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=27012166&loc=d3e187085-122770

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

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- Definition

Total units issued during the year due to the sale of units. All partners include general, limited and preferred partners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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=27012166&loc=d3e187085-122770

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

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- Definition

The number of units sold in a private placement of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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=27012166&loc=d3e187171-122770

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-Name Accounting Standards Codification
-Topic 505
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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