Note 3 - Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Amortized cost, due in one year or less, available for sale securities	$ 1,755
Fair value, due in one year or less, available for sale securities	1,730
Amortized cost, due after one year through five years, available for sale securities	154,209
Fair value, due after one year through five years, available for sale securities	140,650
Amortized cost, due after five years through ten years, available for sale securities	293,046
Fair value, due after five years through ten years, available for sale securities	239,668
Amortized cost, due after ten years, available for sale securities	253,073
Fair value, due after ten years, available for sale securities	209,504
Amortized cost, total securities available for sale	702,083	$ 759,917
Fair value, total securities available for sale	$ 591,552	$ 656,852

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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