Balance Sheet Detail - Schedule of Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, plant and equipment, net:
Property, plant and equipment, gross	$ 20,270	$ 17,201
Less: accumulated depreciation and amortization	(13,130)	(11,271)
Less: government grants	(371)	(412)
Property, plant and equipment, net	6,769	5,518
Furniture and fixtures
Property, plant and equipment, net:
Property, plant and equipment, gross	10,803	8,029
Machinery and equipment
Property, plant and equipment, net:
Property, plant and equipment, gross	2,550	3,553
Leasehold improvements
Property, plant and equipment, net:
Property, plant and equipment, gross	4,267	3,715
Computers and software
Property, plant and equipment, net:
Property, plant and equipment, gross	1,990	922
Others
Property, plant and equipment, net:
Property, plant and equipment, gross	$ 660	$ 982

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