Restructuring (Restructuring Liability) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restructuring Liability [Roll Forward]
Utilization	$ 16.9	$ (31.7)	$ (17.5)
2020 Repositioning
Restructuring Liability [Roll Forward]
Utilization	3.7	(31.5)	0.0
2019 Repositioning
Restructuring Liability [Roll Forward]
Utilization	(0.1)	(6.1)	(9.9)
2017 Repositioning
Restructuring Liability [Roll Forward]
Utilization	13.3	6.2	(2.3)
Other Restructuring
Restructuring Liability [Roll Forward]
Utilization	0.0	0.0	(5.3)
Severance
Restructuring Liability [Roll Forward]
Beginning balance	24.9	22.4
Expense (Gain)	0.1	27.2
Adjustment	(1.4)	1.4
Utilization	(11.4)	(26.1)
Ending balance	12.2	24.9	22.4
Severance | 2020 Repositioning
Restructuring Liability [Roll Forward]
Beginning balance	4.2	0.0
Expense (Gain)	0.0	26.9
Adjustment	(0.9)	0.0
Utilization	(3.3)	(22.7)
Ending balance	0.0	4.2	0.0
Severance | 2019 Repositioning
Restructuring Liability [Roll Forward]
Beginning balance	16.0	9.9
Expense (Gain)	0.1	0.0
Adjustment	0.0	6.1
Utilization	(4.6)	0.0
Ending balance	11.5	16.0	9.9
Severance | 2017 Repositioning
Restructuring Liability [Roll Forward]
Beginning balance	4.7	12.5
Expense (Gain)	0.0	0.0
Adjustment	(0.5)	(4.7)
Utilization	(3.5)	(3.1)
Ending balance	0.7	4.7	12.5
Severance | Other Restructuring
Restructuring Liability [Roll Forward]
Beginning balance	0.0	0.0
Expense (Gain)	0.0	0.3
Adjustment	0.0	0.0
Utilization	0.0	(0.3)
Ending balance	$ 0.0	$ 0.0	$ 0.0