Inventories (Tables)

12 Months Ended

Dec. 31, 2018

Inventory Disclosure [Abstract]

Schedule of inventories

Inventories consist of the following (in thousands):

	December 31,
	2018		2017
Raw materials	$	64,256	$	87,927
Work-in-process	15,211		6,500
Total	$	79,467	$	94,427