Inventories (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Inventory Disclosure [Abstract]
Finished goods	$ 330,500,000	$ 331,900,000
Work in process	10,000,000	5,500,000
Raw materials and repair parts	229,100,000	199,200,000
Total	569,600,000	536,600,000
Excess of current cost over last-in, first-out cost	(59,800,000)	(52,400,000)
Total inventories, net	509,800,000	484,200,000
Pre-tax income (loss) from LIFO inventory liquidations	0	0	$ 200,000
Reserve balance obsolete and slow moving inventories	$ 16,500,000	$ 20,100,000