Note 4 - Inventories - Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Raw materials	$ 15,547	$ 22,759
Work-in-process	9,787	8,366
Finished goods	2,621	2,915
Inventory, Gross, Total	27,955	34,040
Less: Reserve for excess and obsolete inventory	(2,475)	(2,177)
Net inventories	$ 25,480	$ 31,863

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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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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

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