Note 5 - Trade Accounts Receivable - Trade Accounts Receivable Table (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Trade accounts receivable	$ 147	$ 505
Less: Allowance for doubtful accounts	0	(234)
Trade accounts receivable	$ 147	$ 271

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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