Note 3 - Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Amortized cost, due in one year or less, available for sale securities	$ 3,229
Fair value, due in one year or less, available for sale securities	3,172
Amortized cost, due after one year through five years, available for sale securities	148,141
Fair value, due after one year through five years, available for sale securities	138,200
Amortized cost, due after five years through ten years, available for sale securities	316,859
Fair value, due after five years through ten years, available for sale securities	273,664
Amortized cost, due after ten years, available for sale securities	271,036
Fair value, due after ten years, available for sale securities	236,011
Amortized cost, total securities available for sale	739,265	$ 759,917
Fair value, total securities available for sale	$ 651,047	$ 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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