Note 4 - Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Amortized cost, due in one year or less, available for sale securities	$ 63,135
Fair value, due in one year or less, available for sale securities	63,095
Amortized cost, due after one year through five years, available for sale securities	155,427
Fair value, due after one year through five years, available for sale securities	155,253
Amortized cost, due after five years through ten years, available for sale securities	89,199
Fair value, due after five years through ten years, available for sale securities	90,239
Amortized cost, due after ten years, available for sale securities	85,476
Fair value, due after ten years, available for sale securities	87,760
Amortized cost, total securities available for sale	393,237	$ 431,428
Fair value, total securities available for sale	$ 396,347	$ 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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