Note 4 - Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Amortized cost, due in one year or less, available for sale securities	$ 1,377
Fair value, due in one year or less, available for sale securities	1,396
Amortized cost, due after one year through five years, available for sale securities	5,431
Fair value, due after one year through five years, available for sale securities	5,550
Amortized cost, due after five years through ten years, available for sale securities	229,995
Fair value, due after five years through ten years, available for sale securities	232,759
Amortized cost, due after ten years, available for sale securities	370,714
Fair value, due after ten years, available for sale securities	378,051
Amortized cost, total securities available for sale	607,517	$ 530,075
Fair value, total securities available for sale	$ 617,756	$ 546,742

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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