Employee Incentive Plans - Restricted and Performance Awards (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Unvested unit-based awards
Number of Units
Non-vested, beginning of period (in shares)		6,775,186		6,775,186
Granted (in shares)				1,290,501
Vested (in shares)				(2,240,049)
Forfeited (in shares)				(230,507)
Non-vested, end of period (in shares)	5,595,131			5,595,131
Aggregate intrinsic value, end of period	$ 59.3			$ 59.3
Weighted Average Grant-Date Fair Value
Non-vested, beginning of period (in dollars per share)		$ 5.89		$ 5.89
Granted (in dollars per share)				10.81
Vested (in dollars per share)				6.04
Forfeited (in dollars per share)				6.17
Non-vested, end of period (in dollars per share)	$ 6.95			$ 6.95
Units withheld for payroll taxes (in shares)				668,083
Aggregate intrinsic value of units vested	$ 0.4		$ 0.6	$ 27.5	$ 8.2
Fair value of units vested	0.1		$ 0.5	13.5	11.2
Unrecognized compensation cost related to non-vested restricted incentive units	$ 22.1			$ 22.1
Unrecognized compensation costs, weighted average period for recognition (in years)				1 year 10 months 24 days
Performance units
Number of Units
Non-vested, beginning of period (in shares)		2,979,154		2,979,154
Granted (in shares)				420,128
Vested (in shares)				(899,919)
Non-vested, end of period (in shares)	2,499,363			2,499,363
Aggregate intrinsic value, end of period	$ 26.5			$ 26.5
Weighted Average Grant-Date Fair Value
Non-vested, beginning of period (in dollars per share)		$ 6.44		$ 6.44
Granted (in dollars per share)				11.67
Vested (in dollars per share)				9.03
Non-vested, end of period (in dollars per share)	$ 6.39			$ 6.39
Units withheld for payroll taxes (in shares)				668,829
Aggregate intrinsic value of units vested				$ 22.0	5.6
Fair value of units vested				8.1	$ 11.0
Unrecognized compensation cost related to non-vested restricted incentive units	$ 12.5			$ 12.5
Unrecognized compensation costs, weighted average period for recognition (in years)				1 year 9 months 18 days
Performance Units:
Beginning TSR Price (in dollars per share)		10.40
Grant-date fair value (in dollars per share)		$ 11.67
Risk-free interest rate (as a percent)		3.76%
Volatility factor (as a percent)		64.00%
Performance units | Minimum
Performance Units:
Percent of units vesting (as a percent)				0.00%
Performance units | Maximum
Performance Units:
Percent of units vesting (as a percent)				200.00%