Note 3 - Summary of Significant Accounting Policies - Operating Lease Expenses and Supplemental Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Long-term operating lease contracts	$ 103	$ 87	$ 193	$ 124
Short-term operating lease contracts	14	15	29	30
Total	$ 117	$ 102	222	$ 154
Operating cash flows used for operating leases (US$’000)			178
Right-of-use assets obtained in exchange for new lease liabilities (US$’000)			$ 259
Weighted-average remaining lease term (Year)	6 years 21 days		6 years 21 days
Weighted-average discount rate	6.00%		6.00%