Note 3 - Investment Securities - Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Due within one year, AFS, amortized cost	$ 1,989	$ 1,082
Due within one year, AFS, fair value	1,962	1,072
Due within one year, HTM, amortized cost	915	915
Due within one year, HTM, fair value	916	915
Due after one year through five years, AFS, amortized cost	34,341	32,452
Due after one year through five years, AFS, fair value	33,525	31,394
Due after one year through five years, HTM, amortized cost	960	960
Due after one year through five years, HTM, fair value	961	961
Due after five years through ten years, AFS, amortized cost	50,883	52,093
Due after five years through ten years, AFS, fair value	47,639	48,229
Due after five years through ten years, HTM, amortized cost	3,536	3,663
Due after five years through ten years, HTM, fair value	3,493	3,536
Due after ten years, AFS, amortized cost	375,119	381,689
Due after ten years, AFS, fair value	322,981	324,472
Due after ten years, HTM, amortized cost	2,637	2,767
Due after ten years, HTM, fair value	2,435	2,510
Total debt securities, AFS, amortized cost	462,332	467,316
Total debt securities, AFS, fair value	406,107	405,167
Total debt securities, HTM, amortized cost	8,048	8,305
Total debt securities, HTM, fair value	$ 7,805	$ 7,922