Note 3 - Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Amortized cost, due in one year or less, available for sale securities	$ 2,779
Fair value, due in one year or less, available for sale securities	2,738
Amortized cost, due after one year through five years, available for sale securities	139,168
Fair value, due after one year through five years, available for sale securities	129,798
Amortized cost, due after five years through ten years, available for sale securities	328,812
Fair value, due after five years through ten years, available for sale securities	279,880
Amortized cost, due after ten years, available for sale securities	289,158
Fair value, due after ten years, available for sale securities	244,436
Amortized cost, total securities available for sale	759,917	$ 682,467
Fair value, total securities available for sale	$ 656,852	$ 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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