Restructuring and Restructuring Related Charges (Accrued Liability) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restructuring Reserve [Roll Forward]
Balance at beginning of period	$ 4.1	$ 4.2
Amount of total that represents cash charges	(0.3)	7.6	$ 8.1
Less: Payments	2.5	7.7
Balance at end of period	1.3	4.1	4.2
Termination benefits
Restructuring Reserve [Roll Forward]
Balance at beginning of period	3.4	3.5
Amount of total that represents cash charges	(0.4)	7.0
Less: Payments	2.2	7.1
Balance at end of period	0.8	3.4	3.5
Contract termination costs
Restructuring Reserve [Roll Forward]
Balance at beginning of period	0.2	0.0
Amount of total that represents cash charges	0.0	0.2
Less: Payments	0.2	0.0
Balance at end of period	0.0	0.2	0.0
Other restructuring costs
Restructuring Reserve [Roll Forward]
Balance at beginning of period	0.5	0.7
Amount of total that represents cash charges	0.1	0.4
Less: Payments	0.1	0.6
Balance at end of period	$ 0.5	$ 0.5	$ 0.7