Note 5 - Property, Plant and Equipment - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Property, plant and equipment, gross	$ 436	$ 436
Less accumulated depreciation	374	316
Property, plant and equipment, net	62	120
Machinery and Equipment [Member]
Property, plant and equipment, gross	$ 13	13
Machinery and Equipment [Member] | Minimum [Member]
Property, plant and equipment, Depreciable Lives (Year)	3 years
Machinery and Equipment [Member] | Maximum [Member]
Property, plant and equipment, Depreciable Lives (Year)	7 years
Furniture and Fixtures [Member]
Property, plant and equipment, gross	$ 423	$ 423
Furniture and Fixtures [Member] | Minimum [Member]
Property, plant and equipment, Depreciable Lives (Year)	5 years
Furniture and Fixtures [Member] | Maximum [Member]
Property, plant and equipment, Depreciable Lives (Year)	7 years