Note 5 - Operating Leases - Amount Related to Operating Lease Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating cash flows from operating leases	$ 868	$ 587
Right of use assets obtained in exchange for new operating lease liabilities	4,364
Right of use assets obtained in exchange for new operating lease liabilities	$ 4,402	$ 1,047
Weighted-average remaining lease term of operating leases (in years) (Year)	10 years 9 months 18 days	12 years 6 months
Weighted-average discount rate of operating leases	2.40%	3.20%