Note 3 - Securities - Amortized Cost and Estimated Fair Value by Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Due in one year or less, Amortized cost	$ 52,314
Due in one year or less, Fair value	52,315
Due after one year through five years, Amortized cost	185,555
Due after one year through five years, Fair value	185,333
Due after five years through ten years, Amortized cost	84,768
Due after five years through ten years, Fair value	84,381
Due after ten years, Amortized cost	14,021
Due after ten years, Fair value	14,128
Debt Securities, Available-for-sale, Amortized Cost	694,639	$ 455,992
Securities available for sale, at fair value	692,467	$ 466,091
Mortgage-backed and CMOs [Member]
Mortgage-backed and CMOs, Amortized cost	357,981
Mortgage-backed and CMOs, Fair value	$ 356,310

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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