Balance Sheet Details - Schedule of Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 53,744	$ 52,261
Accumulated depreciation	(35,169)	(33,387)
Total property, plant and equipment, net	18,575	18,874
Land and Building [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	2,584	2,584
Machinery and Equipment [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	27,979	29,097
Furniture and Fixtures [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	3,236	3,226
Computer Equipment and Software [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	10,489	7,906
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 9,456	$ 9,448

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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