Note 3 - Securities - Expected Maturities of Investment Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Available-for-sale securities, amortized cost, one year or less	$ 11,616
Available-for-sale securities, fair value, one year or less	11,787
Available-for-sale securities, amortized cost, one year through five years	119,976
Available-for-sale securities, fair value, one year through five years	122,928
Available-for-sale securities, amortized cost, five years through ten years	186,265
Available-for-sale securities, fair value, five years through ten years	185,830
Available-for-sale securities, amortized cost, after ten years	195,567
Available-for-sale securities, fair value, after ten years	196,830
Available-for-sale securities, amortized cost, total	513,424	$ 436,249
Available-for-sale securities, fair value, total	$ 517,375

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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