Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Inventories
Raw materials	$ 3,845	$ 3,476
Work in progress	2,704	6,155
Finished goods	4,259	2,470
Inventory at cost	10,808	12,101
Inventory reserve	(441)	(369)
Inventories net	$ 10,367	$ 11,732

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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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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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