Note 4 - Accounts Receivable, Net - Accounts Receivable, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Accounts receivable	$ 6,364	$ 6,408
Allowance for doubtful accounts	(3,844)	(3,148)
Accounts receivable, net	$ 2,520	$ 3,260

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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