Note 6 - Accounts Receivable, Net - Summary of Accounts Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Gross accounts receivable	$ 2,917	$ 2,274
Allowance for uncollectible accounts	(1,802)	(1,654)
Total accounts receivable, net	$ 1,115	$ 620