Debt - Components (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Short-term debt:
Total short-term debt	$ 918	$ 1,715
Long-term debt:
PAA senior notes, net of unamortized discounts and debt issuance costs of $69 and $76, respectively	9,881	9,874
Other long-term debt	608	250
Total long-term debt	10,489	10,124
Total debt	11,407	11,839
Senior notes
Long-term debt:
PAA senior notes, net of unamortized discounts and debt issuance costs of $69 and $76, respectively	9,881	9,874
Unamortized discounts and debt issuance costs	69	76
Debt instrument face value	9,900	10,300
Commercial paper notes
Long-term debt:
Other long-term debt	$ 605	$ 247
Weighted average interest rate, long-term	2.40%	1.60%
Other
Long-term debt:
Other long-term debt	$ 3	$ 3
Level 2 | Senior notes
Long-term debt:
Debt instrument fair value	10,000	10,400
Commercial paper notes
Short-term debt:
Short-term notes and borrowings	$ 93	$ 563
Weighted average interest rate, short-term	2.40%	1.60%
Other
Short-term debt:
Total short-term debt	$ 72	$ 2
Senior secured hedged inventory facility | Credit facility
Short-term debt:
Short-term notes and borrowings	$ 753	$ 750
Weighted average interest rate, short-term	2.30%	1.80%
6.13 percent senior notes due January 2017 | Senior notes
Short-term debt:
Senior notes, current		$ 400
Long-term debt:
Debt instrument, interest rate		6.13%
6.50% senior notes due May 2018 | Senior notes
Long-term debt:
Debt instrument face value	$ 600
Debt instrument, interest rate	6.50%
Exchange Traded
Short-term debt:
Total short-term debt	$ 194	$ 410