Income Taxes (Taxes by Jurisdiction) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Current Income Tax Expense (Benefit)	$ 0.4	$ 0.5
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	(39.5)	(1.9)
Provision (benefit) for income taxes	(39.1)	(1.4)
Domestic Tax Authority [Member]
Current Income Tax Expense (Benefit)	0.0	0.0
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	(40.7)	0.0
State and Local Jurisdiction [Member]
Current Income Tax Expense (Benefit)	0.4	0.5
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	1.2	(1.9)
Foreign Tax Authority [Member]
Current Income Tax Expense (Benefit)	0.0	0.0
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	$ 0.0	$ 0.0