Note 1 - Organization and Summary of Significant Accounting Policies - Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment, Gross	$ 5,499	$ 3,828
Accumulated depreciation	(3,322)	(2,315)
Property and equipment, net	2,177	1,513
Machinery and Equipment [Member]
Property, Plant and Equipment, Gross	4,995	3,321
Furniture and Fixtures [Member]
Property, Plant and Equipment, Gross	$ 203	194
Building [Member]
Useful life (Year)	39 years
Property, Plant and Equipment, Gross	$ 301	$ 313
Minimum [Member] \| Machinery and Equipment [Member]
Useful life (Year)	3 years
Minimum [Member] \| Furniture and Fixtures [Member]
Useful life (Year)	5 years
Maximum [Member] \| Machinery and Equipment [Member]
Useful life (Year)	5 years
Maximum [Member] \| Furniture and Fixtures [Member]
Useful life (Year)	7 years

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.

+ References

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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