Note 4 - Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Amortized cost, due in one year or less, available for sale securities	$ 61,522
Fair value, due in one year or less, available for sale securities	61,525
Amortized cost, due after one year through five years, available for sale securities	57,871
Fair value, due after one year through five years, available for sale securities	58,039
Amortized cost, due after five years through ten years, available for sale securities	90,075
Fair value, due after five years through ten years, available for sale securities	90,903
Amortized cost, due after ten years, available for sale securities	121,044
Fair value, due after ten years, available for sale securities	123,683
Amortized cost, total securities available for sale	330,512	$ 431,428
Fair value, total securities available for sale	$ 334,150	$ 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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