Note 3 - Securities - Expected Maturities of Investment Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Amounts maturing in:
Available-for-sale securities, amortized cost, one year or less	$ 1,379
Available-for-sale securities, fair value, one year or less	1,384
Available-for-sale securities, amortized cost, after one year through five years	102,007
Available-for-sale securities, fair value, after one year through five years	102,065
Available-for-sale securities, amortized cost, after five years through ten years	110,636
Available-for-sale securities, fair value, after five years through ten years	110,180
Available-for-sale securities, amortized cost, after ten years	80,796
Available-for-sale securities, fair value, after ten years	80,488
Available-for-sale securities, amortized cost, total	294,818	$ 261,198
Available-for-sale securities, fair value, total	$ 294,117

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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