(Deficit) Equity - Schedule of Distributions Declared and/or Paid (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended													12 Months Ended
	Apr. 01, 2020	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 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, 2018	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Distribution Made To Limited Partner [Line Items]
Distributions per Limited Partner unit (in dollars per share)		$ 0.30000	$ 0.30000	$ 0.30000	$ 0.46000	$ 0.46000	$ 0.46000	$ 0.46000	$ 0.46000	$ 0.46000	$ 0.44500	$ 0.43000	$ 0.41500	$ 0.40000	$ 1.36	$ 1.84	$ 1.75
Distributions payable period threshold	60 days
Preferred unitholder’s interest in net income		$ 48													$ 48	$ 36	$ 0
Distribution to holders of incentive distribution rights waived											$ 16	$ 17	$ 17				$ 50
Distributions declared and/or paid		130	$ 130	$ 130	$ 173	$ 173	$ 173	$ 173	$ 162	$ 162	140	131	119	$ 129
Preferred Units
Distribution Made To Limited Partner [Line Items]
Distributions per Limited Partner unit (in dollars per share)	$ 0.2363														$ 0.9452	$ 0.7089
Shell Midstream Partners L.P.
Distribution Made To Limited Partner [Line Items]
Aggregate percentage of interest															2.00%
Common Units | General Public
Distribution Made To Limited Partner [Line Items]
Distributions declared and/or paid		37	37	37	57	57	57	57	57	57	56	53	51	49
Unit distribution (in units)															0
Common Units | Shell Pipeline Company L P
Distribution Made To Limited Partner [Line Items]
Distributions declared and/or paid		81	81	81	104	104	104	104	50	50	48	47	42	40
Unit distribution (in units)															0
General Partner SPLC
Distribution Made To Limited Partner [Line Items]
Distributions declared and/or paid		$ 0	0	0	0	0	0	0	3	3	3	3	3	3
Unit distribution (in units)															0
General Partner SPLC | Partnership Interests Restructuring Agreement
Distribution Made To Limited Partner [Line Items]
Distributions payable, amount waved	$ 20
General Partner SPLC | Economic Interest
Distribution Made To Limited Partner [Line Items]
Noncontrolling interest	2.00%	2.00%													2.00%
General Partner SPLC | General Partner IDR's
Distribution Made To Limited Partner [Line Items]
Distributions declared and/or paid		$ 0	0	0	0	0	0	0	52	52	33	28	23	37
Preferred Units | Shell Pipeline Company L P
Distribution Made To Limited Partner [Line Items]
Distributions declared and/or paid		$ 12	$ 12	$ 12	$ 12	$ 12	$ 12	$ 12	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0