Note 9 - Commitments and Contingencies - Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Current lease cost	$ 82	$ 55
Long-term lease cost	1,026	1,107
Total operating lease cost	1,108	1,162
Amortization of right-of-use assets	64	189
Interest on lease liabilities	6	19
Total finance lease cost	$ 70	$ 208
Weighted-average lease term (years), operating (Year)	3 years 5 months 1 day	4 years 29 days
Weighted-average discount rate, operating	6.09%	6.08%
Weighted-average lease term (years), financing (Year)	2 years 4 months 6 days	2 years 1 month 2 days
Weighted-average discount rate, financing	5.67%	5.94%