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, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Long-term operating lease contracts	$ 87	$ 2	$ 124	$ 5
Short-term operating lease contracts	15	35	30	79
Total	$ 102	$ 37	154	$ 84
Operating cash flows used for operating leases (US$’000)			63
Right-of-use assets obtained in exchange for new lease liabilities (US$’000)			$ 2,179
Weighted-average remaining lease term (Year)	7 years 7 months 17 days		7 years 7 months 17 days
Weighted-average discount rate	6.00%		6.00%