Restructuring and Repositioning Expenses, Asset Write Offs - Restructuring Costs by Segment (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Restructuring Cost and Reserve [Line Items]
Total restructuring expenses and asset write offs from continuing operations	$ 6.5	$ 0.4	$ 14.1	$ 3.5
Operating Segments | SCC
Restructuring Cost and Reserve [Line Items]
Total restructuring expenses and asset write offs from continuing operations	3.1	0.3	6.0	2.6
Operating Segments | SBM
Restructuring Cost and Reserve [Line Items]
Total restructuring expenses and asset write offs from continuing operations	1.9	0.1	3.7	0.9
Corporate
Restructuring Cost and Reserve [Line Items]
Total restructuring expenses and asset write offs from continuing operations	$ 1.5	$ 0.0	$ 4.4	$ 0.0