Note 4 - Accounts Receivable, Net - Accounts Receivable, Net (Details) - USD ($) $ in Thousands		Jun. 30, 2021	Dec. 31, 2020
Accounts receivable		$ 5,914	$ 6,654
Allowance for doubtful accounts	[1]	(2,207)	(4,247)
Accounts receivable, net	[1]	$ 3,707	$ 2,407

[1] All of the VIEs' assets can be used to settle obligations of their primary beneficiary. Liabilities recognized as a result of consolidating these VIEs do not represent additional claims on the Company's general assets (Note 2).