Accrued Liabilities - Third Parties - Schedule of Accrued Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Transportation, project engineering	$ 6.0	$ 4.2
Property taxes	4.5	0.6
Professional fees	0.5	0.3
Other accrued liabilities	2.5	1.8
Accrued liabilities - third parties	$ 13.5	$ 6.9	[1]

[1] Prior period financial information has been retrospectively adjusted for the acquisition of the Shell Delta, Na Kika and Refinery Gas Pipeline Operations.