Note 3 - Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Amortized cost, due in one year or less, available for sale securities	$ 71,303
Fair value, due in one year or less, available for sale securities	71,013
Amortized cost, due after one year through five years, available for sale securities	181,186
Fair value, due after one year through five years, available for sale securities	177,141
Amortized cost, due after five years through ten years, available for sale securities	85,379
Fair value, due after five years through ten years, available for sale securities	84,584
Amortized cost, due after ten years, available for sale securities	93,560
Fair value, due after ten years, available for sale securities	92,272
Amortized cost, total securities available for sale	431,428	$ 336,075
Fair value, total securities available for sale	$ 425,010	$ 331,387

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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