Related Party Transactions - Schedule of Condensed Combined Statement of Operations (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015		Sep. 30, 2016	Sep. 30, 2015
Related Party Transaction [Line Items]
Operations and maintenance – related parties	$ 5.3	$ 4.5	[1]	$ 15.9	$ 14.2	[1]
General and administrative – related parties	5.7	6.3	[1]	17.3	17.8	[1]
Management Agreement
Related Party Transaction [Line Items]
Payment for general administrative services	1.9	1.8		5.8	5.4
Omnibus Agreement
Related Party Transaction [Line Items]
Payment for general administrative services	$ 2.2	$ 2.1		$ 6.4	$ 6.4

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