Note 4 - Property and Equipment - Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Property, plant, and equipment, gross	$ 1,036	$ 1,036
Accumulated depreciation	(767)	(725)
Property, Plant and Equipment, Net	269	311
Machinery and Equipment [Member]
Property, plant, and equipment, gross	$ 41	41
Useful life (Year)	5 years
Trade Show Booth [Member]
Property, plant, and equipment, gross	$ 202	202
Useful life (Year)	5 years
Office Equipment [Member]
Property, plant, and equipment, gross	$ 539	539
Useful life (Year)	5 years
Leasehold Improvements [Member]
Property, plant, and equipment, gross	$ 254	$ 254

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 10
-Topic 360
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482099/360-10-50-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481372/852-10-55-10

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(8))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 360
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480842/942-360-50-1

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant