Note 5 - Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021
Right-of-use lease assets	$ 1,431	$ 1,598	$ 1,712
Current portion of operating lease liability	355	357	348
Operating lease liability, net of current portion	1,196	$ 1,363	1,487
Total operating lease liabilities	$ 1,551		$ 1,835
Weighted average remaining lease term (years) (Year)	4 years 8 months 12 days		5 years 8 months 12 days
Weighted average discount rate	8.50%		8.50%