Note 4 - Summary of Significant Accounting Policies - Operating Lease Expenses and Supplemental Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Long-term operating lease contracts	$ 133	$ 90
Short-term operating lease contracts	6	15
Total	139	105
Operating cash flows used for operating leases (US$’000)	122	86
Right-of-use assets obtained in exchange for new lease liabilities (US$’000)	$ 0	$ 0
Weighted-average remaining lease term (Year)	5 years 7 months 13 days	6 years 10 months 24 days
Weighted-average discount rate	6.00%	6.00%