Inventories (Tables)

3 Months Ended

Mar. 31, 2018

Inventory Disclosure [Abstract]

Schedule of inventories

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

	March 31, 2018		December 31, 2017
Raw materials	$	32,454	$	26,648
Work in process and sub-assemblies		42,353		31,060
Finished goods		17,817		18,060
	$	92,624	$	75,768