Note 3 - Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Amortized cost, due in one year or less, available for sale securities	$ 13,749
Fair value, due in one year or less, available for sale securities	13,419
Amortized cost, due after one year through five years, available for sale securities	180,902
Fair value, due after one year through five years, available for sale securities	166,926
Amortized cost, due after five years through ten years, available for sale securities	273,587
Fair value, due after five years through ten years, available for sale securities	232,336
Amortized cost, due after ten years, available for sale securities	225,140
Fair value, due after ten years, available for sale securities	197,287
Amortized cost, total securities available for sale	693,378	$ 697,786
Fair value, total securities available for sale	$ 609,968	$ 618,601

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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