Note 4 - Securities - Expected Maturities of Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Available-for-sale securities, amortized cost, one year or less	$ 54
Available-for-sale securities, fair value, one year or less	54
Available-for-sale securities, amortized cost, one year through five years	80,796
Available-for-sale securities, fair value, one year through five years	79,726
Available-for-sale securities, amortized cost, five years through ten years	108,251
Available-for-sale securities, fair value, five years through ten years	105,923
Available-for-sale securities, amortized cost, after ten years	72,097
Available-for-sale securities, fair value, after ten years	71,225
Available-for-sale securities, amortized cost, total	261,198	$ 267,395
Available-for-sale securities, fair value, total	$ 256,928

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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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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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