Restructuring Restructuring (Details) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)
Restructuring Cost and Reserve [Line Items]
Severance Costs		$ 12.8
Employees affected		315
Restructuring Reserve	$ 7.0	$ 7.0		$ 8.2	$ 10.2
Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Severance Costs	2.3	$ 6.2
Employees affected		250
2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Severance Costs			$ 3.7
Employees affected			760
buw Acquisition [Member]
Restructuring Cost and Reserve [Line Items]
Severance Costs	0.1	$ 1.1
Restructuring Reserve	$ 0.4	$ 0.4		$ 0.5	$ 0.5