Inventories (Tables)

6 Months Ended

Jun. 30, 2019

Inventory Disclosure [Abstract]

Schedule of inventories

Inventories, net of inventory write-downs, consist of the following for the periods indicated (in thousands):

	June 30, 2019		December 31, 2018
Raw materials	$	26,581	$	30,214
Work in process and sub-assemblies		48,008		49,192
Finished goods		6,886		13,850
Total inventories	$	81,475	$	93,256