Note 3 - Securities - Expected Maturities of Investment Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Amounts maturing in:
Available-for-sale securities, amortized cost, one year or less	$ 7,404
Available-for-sale securities, fair value, one year or less	7,391
Available-for-sale securities, amortized cost, after one year through five years	154,239
Available-for-sale securities, fair value, after one year through five years	155,696
Available-for-sale securities, amortized cost, after five years through ten years	62,183
Available-for-sale securities, fair value, after five years through ten years	62,906
Available-for-sale securities, amortized cost, after ten years	45,197
Available-for-sale securities, fair value, after ten years	46,348
Available-for-sale securities, amortized cost, total	269,023	$ 261,198
Available-for-sale securities, fair value, total	$ 272,341

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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