Equity - At-the-Market Program (Details) - USD ($)						3 Months Ended	12 Months Ended
	Jun. 09, 2016	May 23, 2016	Mar. 29, 2016	Mar. 02, 2016	May 18, 2015	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Issuance of common units, maximum (in units)				$ 300,000,000
Units issued in connection with private placement (in units)							765,307	7,849,294
Net proceeds from public offerings								$ 297,400,000
Consideration for units issued in connection with private placement							$ 9,800,000	$ 6,100,000	$ 0
Aggregate percentage of general partner interest							2.00%
Shell Treasury Center West Inc | Five Year Revolver
Class of Stock [Line Items]
Debt instrument term							5 years
Shell Treasury Center West Inc | 364 Day Revolver
Class of Stock [Line Items]
Debt instrument term							364 days
May 2016 Acquisition
Class of Stock [Line Items]
Consideration for units issued in connection with private placement		$ 7,100,000
Common Units
Class of Stock [Line Items]
Units issued in connection with private placement (in units)					7,692,308
Gross proceed issuance of private placement offering					$ 300,000,000
Common units per share (in units per share)					$ 39.00
Placement fees (less than)					$ 2,600,000
General Partner
Class of Stock [Line Items]
Units issued in connection with private placement (in units)					156,986	15,307	15,307	156,986
Consideration for units issued in connection with private placement	$ 1,100,000		$ 8,200,000		$ 6,100,000	$ 500,000
General Public | Common Units
Class of Stock [Line Items]
Units issued in connection with private placement (in units)						750,000	750,000	7,692,308
Net proceeds from public offerings						$ 25,400,000
Gross proceed issuance of private placement offering						$ 25,500,000
Common units per share (in units per share)	$ 33.25	$ 33.25	$ 31.75			$ 34.00
Placement fees (less than)	$ 100,000	$ 400,000	$ 200,000			$ 100,000
Shell Pipeline Company L P | Common Units
Class of Stock [Line Items]
Units issued in connection with private placement (in units)							0	0
Shell Pipeline Company L P | General Partner | May 2016 Acquisition
Class of Stock [Line Items]
Aggregate percentage of general partner interest							2.00%