Note 4 - Inventory, Net - Summary of Inventory, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Raw materials	$ 5,142	$ 6,927
Work in progress	252	179
Finished goods	720	31
Inventory, net	$ 6,114	$ 7,137

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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