Note 5 - Property - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Property, plant and equipment, gross	$ 51,224	$ 51,235
Less accumulated depreciation	34,787	34,237
Property and equipment, net	16,437	16,998
Land [Member]
Property, plant and equipment, gross	5,052	5,063
Land Improvements [Member]
Property, plant and equipment, gross	12,943	12,943
Building [Member]
Property, plant and equipment, gross	22,869	22,869
Machinery and Equipment [Member]
Property, plant and equipment, gross	$ 10,360	$ 10,360

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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