Related Party Transactions - Additional Information (Details)		3 Months Ended		12 Months Ended
	Nov. 03, 2014 USD ($)	Mar. 31, 2017 USD ($) credit_facility	Mar. 31, 2016 USD ($)	Dec. 31, 2016
Related Party Transaction [Line Items]
Indemnification liability deductible amount	$ 500,000
Aggregate liability of SPLC	15,000,000	$ 10,700,000
Statute of limitations expirations, number of days				60 days
Revenue from related parties		22,900,000	$ 25,400,000
Gain (loss) from sale of excess allowance oil		300,000	(100,000)
Transportation Services
Related Party Transaction [Line Items]
Revenue from related parties		21,000,000	23,300,000
Storage Services
Related Party Transaction [Line Items]
Revenue from related parties		1,900,000	2,100,000
SPLC
Related Party Transaction [Line Items]
General and administrative - related parties		1,900,000	1,300,000
General insurance expense		$ 1,700,000	900,000
Shell Treasury Center West Inc
Related Party Transaction [Line Items]
Number of credit facilities | credit_facility		3
Shell Treasury Center West Inc | Five Year Revolver
Related Party Transaction [Line Items]
Debt instrument term		5 years
Shell Treasury Center West Inc | Five Year Fixed Facility
Related Party Transaction [Line Items]
Debt instrument term		5 years
Shell Treasury Center West Inc | 364 Day Revolver
Related Party Transaction [Line Items]
Debt instrument term		364 days		364 days
Zydeco, Mars, Bengal, Poseidon and Colonial
Related Party Transaction [Line Items]
Total distributions to general partners		$ 91,000,000	49,700,000
Shell Pipeline Company L P
Related Party Transaction [Line Items]
Payment of general and administrative fee	$ 8,500,000
Zydeco
Related Party Transaction [Line Items]
Total distributions to general partners		$ 39,800,000	$ 20,600,000
SPLC | Zydeco
Related Party Transaction [Line Items]
Noncontrolling Interest		7.50%	37.50%	7.50%