Reorganization and Restructuring (Details) $ in Millions	1 Months Ended	3 Months Ended				12 Months Ended
	Jan. 31, 2016 director	Mar. 31, 2017 USD ($) position	Dec. 31, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) position	Dec. 31, 2015 USD ($)
Reorganization and Restructuring 2016
Restructuring Cost and Reserve [Line Items]
Reorganization and restructuring costs		$ 2.8	$ 18.1
Restructuring Reserve [Roll Forward]
Restructuring Reserve, beginining balance		7.6
Expense (benefit)		2.8
Payments and utilization		(5.3)
Restructuring Reserve, ending balance		5.1	7.6			$ 7.6
2015 Reorganization and Restructuring
Restructuring Cost and Reserve [Line Items]
Reorganization and restructuring costs				$ 2.8			$ 11.6
Positions eliminated across the global workforce | position						1,100
Expected cost savings						$ 20.0
Cumulative pretax charges			18.0			18.0
Asset Related Adjustments | Reorganization and Restructuring 2016
Restructuring Reserve [Roll Forward]
Restructuring Reserve, beginining balance		0.0
Expense (benefit)		1.0
Payments and utilization		(1.0)
Restructuring Reserve, ending balance		0.0	0.0			0.0
Severance Costs | Reorganization and Restructuring 2016
Restructuring Reserve [Roll Forward]
Restructuring Reserve, beginining balance		7.0
Expense (benefit)		1.8
Payments and utilization		(4.5)
Restructuring Reserve, ending balance		4.3	7.0			7.0
Severance Costs | Director | Executive Leadership and Board of Directors Restructuring
Restructuring Cost and Reserve [Line Items]
Reorganization and restructuring costs				$ 3.2	$ 1.8
Positions eliminated across the global workforce | director	2
Lease Terminations | Reorganization and Restructuring 2016
Restructuring Reserve [Roll Forward]
Restructuring Reserve, beginining balance		0.6
Expense (benefit)		0.0
Payments and utilization		0.2
Restructuring Reserve, ending balance		$ 0.8	$ 0.6			$ 0.6
Minimum | Reorganization and Restructuring 2016
Restructuring Cost and Reserve [Line Items]
Positions eliminated across the global workforce | position		800
Expected cost savings		$ 8.0
Cumulative pretax charges		$ 15.0
Maximum | Reorganization and Restructuring 2016
Restructuring Cost and Reserve [Line Items]
Positions eliminated across the global workforce | position		900
Expected cost savings		$ 12.0
Cumulative pretax charges		$ 20.0