Note 4 - Securities - Expected Maturities of Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Amounts maturing in:
Available-for-sale securities, amortized cost, one year or less	$ 6,542
Available-for-sale securities, fair value, one year or less	6,567
Available-for-sale securities, amortized cost, one year through five years	139,442
Available-for-sale securities, fair value, one year through five years	141,580
Available-for-sale securities, amortized cost, five years through ten years	74,651
Available-for-sale securities, fair value, five years through ten years	75,295
Available-for-sale securities, amortized cost, after ten years	62,622
Available-for-sale securities, fair value, after ten years	63,508
Available-for-sale securities, amortized cost, total	283,257	$ 261,198
Available-for-sale securities, fair value, total	$ 286,950

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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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth fiscal year through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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