Restructuring Activities - Restructuring Activities (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Continuing Operations:
Other associated costs	$ 0.7	$ 2.9	$ 2.5	$ 12.7
Restructuring charges	6.6	6.2	22.3	9.2
Total charges	7.5	7.7	25.8	24.2
Capital expenditures	0.1	3.4	0.6	17.3
Continuing Operations
Continuing Operations:
Other associated costs	0.9	2.9	3.5	12.7
Restructuring charges	6.6	6.2	22.3	9.2
Total charges	7.5	9.1	25.8	21.9
Discontinued Operations
Continuing Operations:
Total charges	$ 0.0	$ (1.4)	$ 0.0	$ 2.3