Note 2 - Supplemental Balance-sheet Information - Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Property and equipment, gross	$ 2,956	$ 2,561
Less accumulated depreciation	(2,294)	(1,856)
Property and equipment, net	$ 662	705
Equipment [Member]
Estimated useful life (Year)	5 years
Property and equipment, gross	$ 144	105
Leasehold Improvements [Member]
Property and equipment, gross	$ 725	638
Leasehold Improvements [Member] \| Minimum [Member]
Estimated useful life (Year)	2 years
Leasehold Improvements [Member] \| Maximum [Member]
Estimated useful life (Year)	5 years
Furniture and Fixtures [Member]
Estimated useful life (Year)	7 years
Property and equipment, gross	$ 16	16
Software and Software Development Costs [Member]
Estimated useful life (Year)	3 years
Property and equipment, gross	$ 2,071	$ 1,802

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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