Note 3 - Securities - Amortized Cost and Estimated Fair Value by Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Due in one year or less, Amortized cost	$ 44,859
Due in one year or less, Fair value	43,579
Due after one year through five years, Amortized cost	208,162
Due after one year through five years, Fair value	191,338
Due after five years through ten years, Amortized cost	74,582
Due after five years through ten years, Fair value	65,037
Due after ten years, Amortized cost	15,114
Due after ten years, Fair value	14,015
Debt Securities, Available-for-sale, Amortized Cost	679,111	$ 694,639
Securities available for sale, at fair value	608,062	$ 692,467
Mortgage-backed and CMOs [Member]
Mortgage-backed and CMOs, Amortized cost	336,394
Mortgage-backed and CMOs, Fair value	$ 294,093

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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