Inventories, Net (Tables)

9 Months Ended

Sep. 30, 2017

Inventory Disclosure [Abstract]

Inventories, Net

	December 31, 2016		September 30, 2017
	(In millions)
Raw materials:
Chemicals	$	68.7	$	89.5
Component products		2.7		2.9
Total raw materials		71.4		92.4
Work in process:
Chemicals		22.3		17.8
Component products		9.0		9.7
Total in-process products		31.3		27.5
Finished products:
Chemicals		196.4		163.7
Component products		3.2		2.8
Total finished products		199.6		166.5
Supplies (primarily chemicals)		58.3		66.3
Total	$	360.6	$	352.7