Note 15 - Financial Instrument Commitments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Commitments And Contingencies Disclosure [Line Items]
Total financial instrument commitments	$ 346,770	$ 319,104
Commitments to Extend Credit [Member]
Commitments And Contingencies Disclosure [Line Items]
Total financial instrument commitments	325,449	296,537
Standby Letters of Credit [Member]
Commitments And Contingencies Disclosure [Line Items]
Total financial instrument commitments	$ 21,321	$ 22,567