Note 11 - Leases - Summary of Other Information Related to Operating Leases (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 223	$ 224	$ 672	$ 669
Weighted-average remaining lease term – operating leases (Year)	3 years	3 years 10 months 24 days	3 years	3 years 10 months 24 days
Weighted-average discount rate – operating leases	2.19%	2.19%	2.19%	2.19%