Inventories (Tables)

9 Months Ended

Sep. 30, 2019

Inventory Disclosure [Abstract]

Schedule of Inventory, Current [Table Text Block]

Components of inventories as of September 30, 2019 and December 31, 2018 are as follows: 

	September 30, 2019		December 31, 2018
	(In Thousands)
Finished goods	$	69,326	$	69,762
Raw materials	3,043		3,503
Parts and supplies	46,815		47,386
Work in progress	23,222		22,920
Total inventories	$	142,406	$	143,571