Note 5 - Inventory - Summary of Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Raw materials and supplies	$ 188	$ 217
Finished goods	224	167
Less: Reserve for excess and obsolete inventory	(110)	(104)
Total inventory, net	$ 302	$ 280

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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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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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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Amount of valuation reserve for inventory.

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