Inventories (Schedule of Inventories) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Finished goods	$ 40.1	$ 38.8
Goods in process	4.9	4.4
Raw materials and supplies	37.2	27.8
Less LIFO reserves	(10.1)	(9.8)
Total inventories, net	$ 72.1	$ 61.2