Inventories (Tables)

6 Months Ended

Jun. 30, 2020

Inventory Disclosure [Abstract]

Schedule of Inventory, Current [Table Text Block]

Components of inventories as of June 30, 2020 and December 31, 2019 are as follows: 

	June 30, 2020		December 31, 2019
	(In Thousands)
Finished goods	$	63,952	$	70,135
Raw materials	4,030		4,125
Parts and supplies	35,814		47,793
Work in progress	11,710		14,457
Total inventories	$	115,506	$	136,510