Employee Incentive Plans - Restricted and Performance Awards (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 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)				1,575,905
Vested (in shares)				(2,413,511)
Forfeited (in shares)				(333,050)
Non-vested, end of period (in shares)	5,604,530			5,604,530
Aggregate intrinsic value, end of period	$ 68.5			$ 68.5
Weighted Average Grant-Date Fair Value
Non-vested, beginning of period (in dollars per share)		$ 5.89		$ 5.89
Granted (in dollars per share)				11.02
Vested (in dollars per share)				6.00
Forfeited (in dollars per share)				6.91
Non-vested, end of period (in dollars per share)	$ 7.22			$ 7.22
Units withheld for payroll taxes (in shares)				735,018
Aggregate intrinsic value of units vested	$ 2.1		$ 11.1	$ 29.6	$ 19.3
Fair value of units vested	1.0		6.1	14.5	17.3
Unrecognized compensation cost related to non-vested restricted incentive units	$ 20.8			$ 20.8
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)				(1,091,523)
Forfeited (in shares)				(81,827)
Non-vested, end of period (in shares)	2,225,932			2,225,932
Aggregate intrinsic value, end of period	$ 27.2			$ 27.2
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)				8.30
Forfeited (in dollars per share)				11.06
Non-vested, end of period (in dollars per share)	$ 6.35			$ 6.35
Units withheld for payroll taxes (in shares)				811,114
Aggregate intrinsic value of units vested	$ 4.1		10.2	$ 26.1	15.8
Fair value of units vested	1.0		$ 4.5	9.1	$ 15.5
Unrecognized compensation cost related to non-vested restricted incentive units	$ 10.0			$ 10.0
Unrecognized compensation costs, weighted average period for recognition (in years)				1 year 7 months 6 days
Performance Units:
Beginning TSR Price (in dollars per share)		11.67
Grant-date fair value (in dollars per share)		$ 10.40
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%