Note 1 - Nature of Operations and Summary of Significant Accounting Policies - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Land	$ 1,306	$ 1,306
Buildings and leasehold improvements	28,207	27,406
Machinery and equipment	29,194	27,497
Total cost	58,707	56,209
Accumulated depreciation and amortization	(34,921)	(31,458)
Property, Plant and Equipment, Net	$ 23,786	$ 24,751

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 of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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