Note 4 - Inventory - Summary of Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Raw materials	$ 2,184	$ 1,777
Work in progress	6,333	4,863
Finished goods	2,373	1,492
Inventory	$ 10,890	$ 8,132

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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