Partners' Capital and Distributions - Issuance of Units by Subsidiaries (Details) - PAA - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
	Jan. 28, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Partners Capital and Distributions
Units Issued (in units)			22,133,904
Net Proceeds			$ 1,099
Period after which issuer may convert to common units	3 years
Series A Convertible Preferred Units
Partners Capital and Distributions
Private placement of units (in units)	61,000,000
Cash purchase price (in dollars per unit)	$ 26.25
Transaction fee due to purchasers	2.00%
Net proceeds from private placement	$ 1,600
Quarterly distribution rate (in dollars per unit)	$ 0.525
Annualized distribution rate (in dollars per unit)	$ 2.10
Period after which unitholders may convert to common units	2 years
Conversion ratio	1
Period after fifth and subsequent anniversaries for distribution rate reset	30 days
Continuous Offering Program
Partners Capital and Distributions
Units Issued (in units)		26,278,288	1,133,904	15,375,810
Net Proceeds		$ 796	$ 58	$ 848
Commissions paid		$ 8	$ 1	$ 9
Underwritten Offering
Partners Capital and Distributions
Units Issued (in units)			21,000,000
Net Proceeds			$ 1,041
US Treasury Rate | Series A Convertible Preferred Units
Partners Capital and Distributions
Distribution rate reset, basis spread on variable rate	5.85%