Note 10 - Financial Instrument Commitments (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Commitments And Contingencies Disclosure [Line Items]
Total financial instrument commitments	$ 409,695	$ 358,824
Commitments to Extend Credit [Member]
Commitments And Contingencies Disclosure [Line Items]
Total financial instrument commitments	389,336	339,312
Standby Letters of Credit [Member]
Commitments And Contingencies Disclosure [Line Items]
Total financial instrument commitments	$ 20,359	$ 19,512