Income Taxes - Components of Income Tax Benefit (Provision) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Current income tax expense	$ (0.8)	$ (1.2)	$ (1.2)	$ (1.5)
Deferred income tax expense	(6.2)	(9.4)	(12.0)	(39.0)
Income tax expense	(7.0)	(10.6)	(13.2)	(40.5)
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Expected income tax expense based on federal statutory tax rate	(6.3)	(8.4)	(16.8)	(38.3)
State income tax expense, net of federal benefit	(0.9)	(1.1)	(2.4)	(4.9)
Unit-based compensation	0.1	0.9	7.8	7.5
Other	0.1	(2.0)	(1.8)	(4.8)
Income tax expense	$ (7.0)	$ (10.6)	$ (13.2)	$ (40.5)