Note 2 - Balance Sheet Details - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property and equipment, gross	$ 1,040	$ 1,244
Less accumulated depreciation and amortization	(918)	(1,132)
Property and equipment, net	122	112
Leasehold Improvements [Member]
Property and equipment, gross	163	114
Furniture and Fixtures [Member]
Property and equipment, gross	268	286
Machinery and Equipment [Member]
Property and equipment, gross	$ 609	$ 844

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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