Balance Sheet Details - Schedule of Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Property Plant And Equipment [Abstract]
Land and building	$ 2,584	$ 2,584
Machinery and equipment	29,789	29,870
Furniture and fixtures	3,143	3,201
Computer equipment and software	5,846	5,444
Leasehold improvements	9,346	9,472
Property, plant and equipment, gross	50,708	50,571
Accumulated depreciation	(33,210)	(33,229)
Total property, plant and equipment, net	$ 17,498	$ 17,342