Income Taxes - Provision/(Benefit) For Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Current
U.S. federal	$ 3.5	$ 3.5	$ 0.7
Foreign	38.2	14.6	36.1
State and local	(1.2)	0.4	1.5
Total current	40.5	18.5	38.3
Deferred
U.S. federal	(1.7)	7.1	78.1
Foreign	(11.4)	(22.6)	(11.7)
State and local	0.3	(4.0)	12.0
Total deferred	(12.8)	(19.5)	78.4
Income tax expense (benefit)	$ 27.7	$ (1.0)	$ 116.7