Goodwill and Intangible Assets - Changes in Carrying Value of Goodwill (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Balance, beginning of period		$ 1,310.2		$ 1,310.2	$ 1,542.2
Goodwill allocation				0.0
Impairment				(1,125.6)	(232.0)	$ 0.0
Balance, end of period	$ 184.6		$ 1,310.2	184.6	1,310.2	1,542.2
Operating Segments | Permian
Goodwill [Roll Forward]
Balance, beginning of period		0.0		0.0	29.3
Impairment			(29.3)
Balance, end of period	184.6		0.0	184.6	0.0	29.3
Operating Segments | North Texas
Goodwill [Roll Forward]
Balance, beginning of period		0.0		0.0	202.7
Impairment			(202.7)
Balance, end of period	0.0		0.0	0.0	0.0	202.7
Operating Segments | Oklahoma
Goodwill [Roll Forward]
Balance, beginning of period		190.3		190.3	190.3
Balance, end of period	0.0		190.3	0.0	190.3	190.3
Operating Segments | Louisiana
Goodwill [Roll Forward]
Balance, beginning of period		0.0		0.0	0.0
Balance, end of period	0.0		0.0	0.0	0.0	0.0
Corporate
Goodwill [Roll Forward]
Balance, beginning of period		1,119.9		1,119.9	1,119.9
Balance, end of period	0.0		1,119.9	0.0	1,119.9	1,119.9
EnLink Midstream Partners, LP | Operating Segments | Permian
Goodwill [Roll Forward]
Balance, beginning of period		0.0		0.0	29.3
Goodwill allocation				184.6
Impairment				0.0	(29.3)
Balance, end of period	184.6		0.0	184.6	0.0	29.3
EnLink Midstream Partners, LP | Operating Segments | North Texas
Goodwill [Roll Forward]
Balance, beginning of period		0.0		0.0	202.7
Goodwill allocation				125.7
Impairment	(125.7)				(202.7)
Balance, end of period	0.0		0.0	0.0	0.0	202.7
EnLink Midstream Partners, LP | Operating Segments | Oklahoma
Goodwill [Roll Forward]
Balance, beginning of period		190.3		190.3	190.3
Goodwill allocation				623.1
Impairment	(813.4)				0.0
Balance, end of period	0.0		190.3	0.0	190.3	190.3
EnLink Midstream Partners, LP | Operating Segments | Louisiana
Goodwill [Roll Forward]
Balance, beginning of period		0.0		0.0	0.0
Goodwill allocation				186.5
Impairment				(186.5)	0.0
Balance, end of period	0.0		0.0	0.0	0.0	0.0
EnLink Midstream Partners, LP | Corporate | Louisiana
Goodwill [Roll Forward]
Impairment		(186.5)
EnLink Midstream Partners, LP | Corporate | Crude and Condensate
Goodwill [Roll Forward]
Balance, beginning of period		$ 1,119.9		1,119.9	1,119.9
Goodwill allocation				(1,119.9)
Impairment				0.0	0.0
Balance, end of period	$ 0.0		$ 1,119.9	$ 0.0	$ 1,119.9	$ 1,119.9