Note 4 - Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Amortized cost, due in one year or less, available for sale securities	$ 3,768
Fair value, due in one year or less, available for sale securities	3,745
Amortized cost, due after one year through five years, available for sale securities	104,168
Fair value, due after one year through five years, available for sale securities	100,560
Amortized cost, due after five years through ten years, available for sale securities	328,929
Fair value, due after five years through ten years, available for sale securities	298,257
Amortized cost, due after ten years, available for sale securities	316,101
Fair value, due after ten years, available for sale securities	279,689
Amortized cost, total securities available for sale	752,966	$ 682,467
Fair value, total securities available for sale	$ 682,251	$ 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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