Inventories Inventories (Tables)

12 Months Ended

Dec. 31, 2018

Inventory [Line Items]

Schedule of Inventory, Current [Table Text Block]

Components of inventories are as follows:

	December 31,
	2018		2017
	(In Thousands)
Finished goods	$	69,762	$	66,377
Raw materials	3,503		4,027
Parts and supplies	47,386		33,632
Work in progress	22,920		11,402
Total inventories	$	143,571	$	115,438