Note 6 - Securities Available for Sale - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Due less than one year, amortized cost	$ 64,284
Due less than one year, fair value	60,418
Due after one year through five years, amortized cost	125,539
Due after one year through five years, fair value	114,722
Due after five years through fifteen years, amortized cost	35,179
Due after five years through fifteen years, fair value	31,466
Due after fifteen years, amortized cost	3
Due after fifteen years, fair value	3
Total, amortized cost	225,005	$ 233,478
Total, fair value	$ 206,609	$ 215,094