Note 2 - Investment Securities - Amortized Cost and Fair Value of Debt Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Securities available for sale, amortized cost, due in one year or less	$ 22,421
Securities available for sale, fair value, due in one year or less	22,316
Securities available for sale, amortized cost, due after one year through five years	50,972
Securities available for sale, fair value, due after one year through five years	51,415
Securities available for sale, amortized cost, due after five years through ten years	32,877
Securities available for sale, fair value, due after five years through ten years	33,809
Securities available for sale, amortized cost, due after ten years	25,772
Securities available for sale, fair value, due after ten years	27,021
Securities available for sale, amortized cost, single maturity	132,042
Securities available for sale, fair value, single maturity	134,561
Securities available for sale, amortized cost, Mortgage-backed securities and CMO	125,544
Securities available for sale, fair value, Mortgage-backed securities and CMO	124,884
Securities available for sale, fair value	259,445	$ 261,841
Debt Securities [Member]
Securities available for sale, amortized cost	257,586
Securities available for sale, fair value	$ 259,445

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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