Note 3 - Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Amortized cost, due in one year or less, available for sale securities	$ 55,186
Fair value, due in one year or less, available for sale securities	55,302
Amortized cost, due after one year through five years, available for sale securities	6,342
Fair value, due after one year through five years, available for sale securities	6,505
Amortized cost, due after five years through ten years, available for sale securities	145,040
Fair value, due after five years through ten years, available for sale securities	144,260
Amortized cost, due after ten years, available for sale securities	228,598
Fair value, due after ten years, available for sale securities	229,196
Amortized cost, total securities available for sale	435,166	$ 431,428
Fair value, total securities available for sale	$ 435,263	$ 425,010

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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