Inventories (Tables)

3 Months Ended

Mar. 31, 2020

Inventory Disclosure [Abstract]

Schedule of Inventory, Current [Table Text Block]

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

	March 31, 2020		December 31, 2019
	(In Thousands)
Finished goods	$	67,824	$	70,135
Raw materials	3,886		4,125
Parts and supplies	38,859		47,793
Work in progress	31,547		14,457
Total inventories	$	142,116	$	136,510