Note 4 - Accounts Receivable, Net - Accounts Receivable, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Accounts receivable	$ 10,481	$ 9,752
Allowance for doubtful accounts	(3,651)	(3,393)
Accounts receivable, net	$ 6,830	$ 6,359

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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