Note 3 - Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Amortized cost, due in one year or less, available for sale securities	$ 1,897
Fair value, due in one year or less, available for sale securities	1,868
Amortized cost, due after one year through five years, available for sale securities	139,460
Fair value, due after one year through five years, available for sale securities	128,835
Amortized cost, due after five years through ten years, available for sale securities	299,548
Fair value, due after five years through ten years, available for sale securities	255,178
Amortized cost, due after ten years, available for sale securities	264,284
Fair value, due after ten years, available for sale securities	228,297
Amortized cost, total securities available for sale	705,189	$ 759,917
Fair value, total securities available for sale	$ 614,178	$ 656,852

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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