Goodwill and Intangible Assets - Changes in Carrying Value of Goodwill (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Balance, beginning of period	$ 2,413.9	$ 2,413.9
Impairment	(873.3)		$ (1,328.2)
Balance, end of period		1,542.2	2,413.9
Operating Segments | Texas
Goodwill [Roll Forward]
Balance, beginning of period	703.5	703.5
Balance, end of period		232.0	703.5
Operating Segments | Oklahoma
Goodwill [Roll Forward]
Balance, beginning of period	190.3	190.3
Balance, end of period		190.3	190.3
Operating Segments | Crude and Condensate
Goodwill [Roll Forward]
Balance, beginning of period	93.2	93.2
Balance, end of period		0.0	93.2
Corporate
Goodwill [Roll Forward]
Balance, beginning of period	1,426.9	1,426.9
Balance, end of period		1,119.9	1,426.9
EnLink Midstream Partners, LP
Goodwill [Roll Forward]
Balance, beginning of period	2,413.9	2,413.9
Impairment		(873.3)
Acquisition adjustment		1.6
Balance, end of period		1,542.2	2,413.9
EnLink Midstream Partners, LP | Operating Segments | Texas
Goodwill [Roll Forward]
Balance, beginning of period	703.5	703.5
Impairment		(473.1)
Acquisition adjustment		1.6
Balance, end of period		232.0	703.5
EnLink Midstream Partners, LP | Operating Segments | Oklahoma
Goodwill [Roll Forward]
Balance, beginning of period	190.3	190.3
Impairment		0.0
Acquisition adjustment		0.0
Balance, end of period		190.3	190.3
EnLink Midstream Partners, LP | Operating Segments | Crude and Condensate
Goodwill [Roll Forward]
Balance, beginning of period	93.2	93.2
Impairment		(93.2)
Acquisition adjustment		0.0
Balance, end of period		0.0	93.2
EnLink Midstream Partners, LP | Corporate
Goodwill [Roll Forward]
Balance, beginning of period	$ 1,426.9	1,426.9
Impairment		(307.0)
Acquisition adjustment		0.0
Balance, end of period		$ 1,119.9	$ 1,426.9