Note 4 - Inventories - Schedule of Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Raw materials	$ 1,898	$ 2,102	$ 1,286
Work-in-process	544	158
Finished products	1,670	1,162	3,009
Total inventories	$ 4,112	$ 3,422	$ 4,295

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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