Restructuring (Restructuring Liability) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restructuring Cost and Reserve [Line Items]
Utilization	$ 0.0	$ (1.6)	$ (22.6)	$ (6.1)
2020 Repositioning Actions
Restructuring Cost and Reserve [Line Items]
Utilization			(24.8)	0.0
2017 Repositioning Actions
Restructuring Cost and Reserve [Line Items]
Utilization			2.5	$ (2.4)
Severance
Restructuring Cost and Reserve [Line Items]
Beginning balance			22.4
Expense (Gain)			21.7
Utilization			(23.1)
Ending balance	23.8		23.8
Severance | 2020 Repositioning Actions
Restructuring Cost and Reserve [Line Items]
Beginning balance			0.0
Expense (Gain)			18.8
Utilization			23.8
Ending balance	5.0		5.0
Severance | 2019 Repositioning Actions
Restructuring Cost and Reserve [Line Items]
Beginning balance			9.9
Expense (Gain)			0.0
Ending balance	9.9		9.9
Severance | 2017 Repositioning Actions
Restructuring Cost and Reserve [Line Items]
Beginning balance			12.5
Expense (Gain)			2.6
Utilization			1.0
Ending balance	8.9		8.9
Severance | Other Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Beginning balance			0.0
Expense (Gain)			0.3
Utilization			(0.3)
Ending balance	0.0		0.0
Other Restructuring Costs
Restructuring Cost and Reserve [Line Items]
Beginning balance			0.2
Expense (Gain)			(0.3)
Utilization			0.5
Ending balance	0.0		0.0
Other Restructuring Costs | 2020 Repositioning Actions
Restructuring Cost and Reserve [Line Items]
Beginning balance			0.0
Expense (Gain)			1.0
Utilization			(1.0)
Ending balance	0.0		0.0
Other Restructuring Costs | 2019 Repositioning Actions
Restructuring Cost and Reserve [Line Items]
Beginning balance			0.0
Expense (Gain)			0.0
Utilization			0.0
Ending balance	0.0		0.0
Other Restructuring Costs | 2017 Repositioning Actions
Restructuring Cost and Reserve [Line Items]
Beginning balance			0.2
Expense (Gain)			(1.3)
Utilization			1.5
Ending balance	0.0		0.0
Other Restructuring Costs | Other Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Beginning balance			0.0
Utilization			0.0
Ending balance	$ 0.0		$ 0.0