Income Taxes - Schedule of Income Tax Expense (Benefit) for Continuing Operations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Current:
Federal	$ 0.0	$ 0.0	$ 0.0
State and local	0.1	0.0	0.0
Foreign	0.0	0.0	0.0
Total current	0.1	0.0	0.0
Deferred:
Federal	(47.0)	(48.3)	(31.0)
State and local	(11.8)	(7.0)	(6.6)
Foreign	0.0	0.0	0.0
Total deferred	(58.8)	(55.3)	(37.6)
Valuation allowance	44.8	38.9	29.6
Total	$ (13.9)	$ (16.4)	$ (8.0)