Pension Plans and Other Postretirement Benefits Pension and Postretirement Plan Contributions (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Defined Benefit Plan Disclosure [Line Items]
Other postretirement benefits payments	$ 0.7	$ 0.8	$ 1.2	$ 1.6
Chemetall Surface Treatment
Defined Benefit Plan Disclosure [Line Items]
Pension contributions		0.9		1.9
Continuing Operations
Defined Benefit Plan Disclosure [Line Items]
Pension contributions	$ 2.7	$ 3.6	$ 5.1	$ 6.0