Debt (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Short-term debt:
Other short-term debt	$ 3	$ 4
Total short-term debt	1,287	1,113
Long-term debt:
Unamortized discounts	(18)	(15)
PAA senior notes, net of unamortized discounts	8,757	6,710
Long-term debt, other	5	5
Total long-term debt	8,762	6,715
Total debt	10,049	7,828
5.25% senior notes due June 2015
Short-term debt:
Senior Notes, Current	150
Long-term debt:
Senior Notes, Noncurrent		150
Debt instrument, interest rate (as a percent)	5.25%	5.25%
3.95% senior notes due September 2015
Short-term debt:
Senior Notes, Current	400
Long-term debt:
Senior Notes, Noncurrent		400
Debt instrument, interest rate (as a percent)	3.95%	3.95%
5.88% senior notes due August 2016
Long-term debt:
Senior Notes, Noncurrent	175	175
Debt instrument, interest rate (as a percent)	5.88%	5.88%
6.13% senior notes due January 2017
Long-term debt:
Senior Notes, Noncurrent	400	400
Debt instrument, interest rate (as a percent)	6.13%	6.13%
6.50% senior notes due May 2018
Long-term debt:
Senior Notes, Noncurrent	600	600
Debt instrument, interest rate (as a percent)	6.50%	6.50%
8.75% senior notes due May 2019
Long-term debt:
Senior Notes, Noncurrent	350	350
Debt instrument, interest rate (as a percent)	8.75%	8.75%
2.60% senior notes due December 2019
Long-term debt:
Senior Notes, Noncurrent	500
Debt instrument, interest rate (as a percent)	2.60%
5.75% senior notes due January 2020
Long-term debt:
Senior Notes, Noncurrent	500	500
Debt instrument, interest rate (as a percent)	5.75%	5.75%
5.00% senior notes due February 2021
Long-term debt:
Senior Notes, Noncurrent	600	600
Debt instrument, interest rate (as a percent)	5.00%	5.00%
3.65% senior notes due June 2022
Long-term debt:
Senior Notes, Noncurrent	750	750
Debt instrument, interest rate (as a percent)	3.65%	3.65%	3.65%
2.85% senior notes due January 2023
Long-term debt:
Senior Notes, Noncurrent	400	400
Debt instrument, interest rate (as a percent)	2.85%	2.85%	2.85%
3.85% senior notes due October 2023
Long-term debt:
Senior Notes, Noncurrent	700	700
Debt instrument, interest rate (as a percent)	3.85%	3.85%
3.60% senior notes due November 2024
Long-term debt:
Senior Notes, Noncurrent	750
Debt instrument, interest rate (as a percent)	3.60%
6.70% senior notes due May 2036
Long-term debt:
Senior Notes, Noncurrent	250	250
Debt instrument, interest rate (as a percent)	6.70%	6.70%
6.65% senior notes due January 2037
Long-term debt:
Senior Notes, Noncurrent	600	600
Debt instrument, interest rate (as a percent)	6.65%	6.65%
5.15% senior notes due June 2042
Long-term debt:
Senior Notes, Noncurrent	500	500
Debt instrument, interest rate (as a percent)	5.15%	5.15%	5.15%
4.30% senior notes due January 2043
Long-term debt:
Senior Notes, Noncurrent	350	350
Debt instrument, interest rate (as a percent)	4.30%	4.30%	4.30%
4.70% senior notes due June 2044
Long-term debt:
Senior Notes, Noncurrent	700
Debt instrument, interest rate (as a percent)	4.70%
4.90% senior notes due February 2045
Long-term debt:
Senior Notes, Noncurrent	650
Debt instrument, interest rate (as a percent)	4.90%
Commercial paper program
Short-term debt:
PAA commercial paper notes, bearing a weighted-average interest rate of 0.46% and 0.33%, respectively	$ 734	$ 1,109
Repayment period	1 year
Weighted average interest rate, short-term (as a percent)	0.46%	0.33%