Note 9 - Details of Selected Balance Sheet Accounts - Summary of Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Raw materials and purchased subassemblies	$ 18,215	$ 18,638
Work-in-process	1,363	1,218
Finished goods	4,372	4,417
Less: reserve for excess and obsolete inventories	(12,919)	(13,006)
Inventories, net	$ 11,031	$ 11,267

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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Amount of valuation reserve for inventory.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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