Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning Balance	$ 36.3	$ 36.0	$ 29.7
Additions based on prior year positions	3.8	1.2	6.5
Decreases due to settlements and/or reduction in reserves	(0.1)	(0.9)	(0.2)
Ending Balance	$ 40.0	$ 36.3	$ 36.0