Reorganization and Restructuring Reorganization and Restructuring - Narrative (Details) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2016 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) position	Dec. 31, 2017 USD ($)
Reorganization and Restructuring 2016
Restructuring Cost and Reserve [Line Items]
Cumulative pretax charges			$ 48.0
Positions eliminated across the global workforce | position			800
Restructuring Reserve [Roll Forward]
Restructuring Reserve, beginning balance		$ 0.7	$ 2.0	$ 7.6
Expense (benefit)	$ 18.1		13.0	17.3
Payments and utilization			(14.3)	(23.1)
Foreign currency exchange effects			0.0	0.2
Restructuring Reserve, ending balance	7.6		0.7	2.0
Other Restructurings
Restructuring Cost and Reserve [Line Items]
Restructuring costs		28.8
Restructuring Reserve [Roll Forward]
Restructuring Reserve, beginning balance		3.3
Expense (benefit)		29.2	7.6	4.6
Payments and utilization		(25.1)
Accrual adjustment		(0.4)
Foreign currency exchange effects		0.0
Restructuring Reserve, ending balance		7.0	3.3
Asset Related Adjustments | Reorganization and Restructuring 2016
Restructuring Reserve [Roll Forward]
Restructuring Reserve, beginning balance		0.0	0.0	0.0
Expense (benefit)			1.7	4.1
Payments and utilization			(1.7)	(4.1)
Foreign currency exchange effects			0.0	0.0
Restructuring Reserve, ending balance	0.0		0.0	0.0
Severance Costs | Reorganization and Restructuring 2016
Restructuring Reserve [Roll Forward]
Restructuring Reserve, beginning balance		0.5	1.6	7.0
Expense (benefit)			11.3	10.4
Payments and utilization			(12.4)	(16.0)
Foreign currency exchange effects			0.0	0.2
Restructuring Reserve, ending balance	7.0		0.5	1.6
Severance Costs | Other Restructurings
Restructuring Reserve [Roll Forward]
Restructuring Reserve, beginning balance		3.3
Expense (benefit)		19.7
Payments and utilization		(15.6)
Accrual adjustment		(0.4)
Foreign currency exchange effects		0.0
Restructuring Reserve, ending balance		7.0	3.3
Lease Terminations | Reorganization and Restructuring 2016
Restructuring Reserve [Roll Forward]
Restructuring Reserve, beginning balance		0.2	0.4	0.6
Expense (benefit)			0.0	0.6
Payments and utilization			(0.2)	(0.8)
Foreign currency exchange effects			0.0	0.0
Restructuring Reserve, ending balance	0.6		0.2	0.4
Benefit Program Termination | Reorganization and Restructuring 2016
Restructuring Reserve [Roll Forward]
Restructuring Reserve, beginning balance		0.0	0.0	0.0
Expense (benefit)			0.0	2.2
Payments and utilization			0.0	(2.2)
Foreign currency exchange effects			0.0	0.0
Restructuring Reserve, ending balance	$ 0.0		0.0	$ 0.0
Modification of Share-based Awards | Other Restructurings
Restructuring Reserve [Roll Forward]
Restructuring Reserve, beginning balance		0.0
Expense (benefit)		7.7
Payments and utilization		(7.7)
Accrual adjustment		0.0
Foreign currency exchange effects		0.0
Restructuring Reserve, ending balance		0.0	0.0
Other Restructuring | Other Restructurings
Restructuring Reserve [Roll Forward]
Restructuring Reserve, beginning balance		0.0
Expense (benefit)		1.8
Payments and utilization		(1.8)
Accrual adjustment		0.0
Foreign currency exchange effects		0.0
Restructuring Reserve, ending balance		0.0	$ 0.0
Minimum | Other Restructurings
Restructuring Cost and Reserve [Line Items]
Expected costs		1.0
Maximum | Other Restructurings
Restructuring Cost and Reserve [Line Items]
Expected costs		$ 3.0