Note 4 - Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Amortized cost, due in one year or less, available for sale securities	$ 1,317
Fair value, due in one year or less, available for sale securities	1,325
Amortized cost, due after one year through five years, available for sale securities	79,070
Fair value, due after one year through five years, available for sale securities	77,180
Amortized cost, due after five years through ten years, available for sale securities	329,371
Fair value, due after five years through ten years, available for sale securities	310,296
Amortized cost, due after ten years, available for sale securities	328,801
Fair value, due after ten years, available for sale securities	310,553
Amortized cost, total securities available for sale	738,559	$ 682,467
Fair value, total securities available for sale	$ 699,354	$ 686,080

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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