Note 2 - Balance Sheet Details - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property and equipment, gross	$ 1,244	$ 1,224
Less accumulated depreciation and amortization	(1,132)	(1,052)
Property and equipment, net	112	172
Leasehold Improvements [Member]
Property and equipment, gross	114	114
Furniture and Fixtures [Member]
Property and equipment, gross	286	268
Machinery and Equipment [Member]
Property and equipment, gross	$ 844	$ 842

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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