Note 4 - Inventories - Schedule of Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Raw materials	$ 12,238	$ 12,435
Work in process	12,547	13,602
Finished goods	6,954	7,015
Total inventories	$ 31,739	$ 33,052

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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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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