Employee Incentive Plans - Restricted and Performance Awards (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended			3 Months Ended		6 Months Ended
	Mar. 31, 2020	Feb. 29, 2020	Jan. 31, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Grant-Date Fair Value (in dollars per share)	$ 1.13		$ 7.69
Beginning TSR Price (in dollars per share)	$ 1.25		$ 6.13
Risk-free interest rate	0.42%		1.62%
Volatility factor	51.00%		37.00%
Unvested restricted units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Non-vested, beginning of period (in shares)			4,063,605			4,063,605
Granted (in shares)		1,144,842				4,673,848
Vested (in shares)						(2,413,687)
Forfeited (in shares)						(478,304)
Non-vested, end of period (in shares)				5,845,462		5,845,462
Aggregate intrinsic value, end of period				$ 14.3		$ 14.3
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Non-vested, beginning of period (in dollars per share)			$ 13.85			$ 13.85
Granted (in dollars per share)						5.55
Vested (in dollars per share)						10.35
Forfeited (in dollars per share)						8.39
Non-vested, end of period (in dollars per share)				$ 9.11		$ 9.11
Vesting period						3 years
Fair value of units vested		$ 5.2
Units withheld for payroll taxes (in shares)						851,940
Unrecognized compensation cost related to non-vested restricted incentive units				$ 29.4		$ 29.4
Unrecognized compensation costs, weighted average period for recognition						1 year 9 months 18 days
Unvested restricted units | ENLC
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Fair value of units vested				6.1	$ 0.5	$ 25.0	$ 13.1
Aggregate intrinsic value of units vested				$ 0.8	0.5	$ 10.9	12.9
Unvested restricted units | EnLink Midstream Partners, LP
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Fair value of units vested							7.2
Aggregate intrinsic value of units vested							8.0
Performance units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Non-vested, beginning of period (in shares)			1,317,856			1,317,856
Granted (in shares)						1,161,986
Vested (in shares)						(178,403)
Forfeited (in shares)						(37,646)
Non-vested, end of period (in shares)				2,263,793		2,263,793
Aggregate intrinsic value, end of period				$ 5.5		$ 5.5
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Non-vested, beginning of period (in dollars per share)			$ 14.22			$ 14.22
Granted (in dollars per share)						7.32
Vested (in dollars per share)						30.56
Forfeited (in dollars per share)						11.81
Non-vested, end of period (in dollars per share)				$ 9.43		$ 9.43
Fair value of units vested				$ 0.5	0.0	$ 5.5	1.9
Units withheld for payroll taxes (in shares)						67,775
Aggregate intrinsic value of units vested				0.0	$ 0.0	$ 0.9	1.8
Unrecognized compensation cost related to non-vested restricted incentive units				$ 14.5		$ 14.5
Unrecognized compensation costs, weighted average period for recognition						1 year 8 months 12 days
Performance units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Percent of units vesting						0.00%
Performance units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Percent of units vesting						200.00%
Performance units | EnLink Midstream Partners, LP
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Fair value of units vested							1.7
Aggregate intrinsic value of units vested							$ 2.1