Note 3 - Securities - Expected Maturities of Investment Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Amounts maturing in:
Available-for-sale securities, amortized cost, one year or less	$ 6,119
Available-for-sale securities, fair value, one year or less	6,127
Available-for-sale securities, amortized cost, one year through five years	113,504
Available-for-sale securities, fair value, one year through five years	117,594
Available-for-sale securities, amortized cost, five years through ten years	88,844
Available-for-sale securities, fair value, five years through ten years	91,394
Available-for-sale securities, amortized cost, after ten years	68,168
Available-for-sale securities, fair value, after ten years	69,962
Available-for-sale securities, amortized cost, total	276,635	$ 283,257
Available-for-sale securities, fair value, total	$ 285,077

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 through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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 second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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