BALANCE SHEET DETAILS - Schedule of Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment
Total	$ 30,671	$ 29,403
Less: accumulated depreciation	(30,051)	(28,311)
Total Property, plant and equipment, net	620	1,092
Leasehold improvements
Property, Plant and Equipment
Total	1,846	1,799
Automobiles
Property, Plant and Equipment
Total	340	319
Computer and Software
Property, Plant and Equipment
Total	4,579	4,764
Equipment and Furniture
Property, Plant and Equipment
Total	$ 23,906	$ 22,521

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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