Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions				3 Months Ended								9 Months Ended			14 Months Ended
	Oct. 19, 2016	Oct. 03, 2016	Sep. 27, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	[1]	Mar. 31, 2015	Sep. 30, 2016	Sep. 30, 2015	[1]	Dec. 31, 2015
Subsequent Event [Line Items]
Distributions paid per limited partner unit (in dollars per unit)				$ 0.26375	$ 0.2500	$ 0.2350	$ 0.2200	$ 0.2050	$ 0.1900		$ 0.1750	$ 0.7488	$ 0.57		$ 0.1042
Mars
Subsequent Event [Line Items]
Interest acquired			20.00%
Odyssey Pipeline L.L.C.
Subsequent Event [Line Items]
Interest acquired			49.00%
October 2016 Acquisitions
Subsequent Event [Line Items]
Consideration transferred			$ 350.0
Subsequent Event
Subsequent Event [Line Items]
Distributions paid per limited partner unit (in dollars per unit)	$ 0.26375
Subsequent Event | Mars
Subsequent Event [Line Items]
Interest acquired		20.00%
Subsequent Event | Odyssey Pipeline L.L.C.
Subsequent Event [Line Items]
Interest acquired		49.00%
Subsequent Event | October 2016 Acquisitions
Subsequent Event [Line Items]
Consideration transferred		$ 350.0
Consideration, cash on hand		50.0
Consideration, funded with borrowings		$ 300.0
Shell Treasury Center West Inc | Five Year Revolver
Subsequent Event [Line Items]
Debt instrument term												5 years

[1] (1) The 2015 financial information has been retrospectively adjusted for the acquisition of the Shell Auger and Lockport Operations.