Note 4 - Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Amortized cost, due in one year or less, available for sale securities	$ 1,799
Fair value, due in one year or less, available for sale securities	1,798
Amortized cost, due after one year through five years, available for sale securities	133,556
Fair value, due after one year through five years, available for sale securities	124,384
Amortized cost, due after five years through ten years, available for sale securities	324,861
Fair value, due after five years through ten years, available for sale securities	276,378
Amortized cost, due after ten years, available for sale securities	305,155
Fair value, due after ten years, available for sale securities	254,850
Amortized cost, total securities available for sale	765,371	$ 682,467
Fair value, total securities available for sale	$ 657,410	$ 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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