Note 7 - Inventory - Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Raw materials	$ 9,132	$ 9,560
Work in process	412	792
Total inventory	9,544	10,352
Allowance for obsolescence	(188)	(265)
Inventory, net of allowance	$ 9,356	$ 10,087

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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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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