Note 2 - Investment Securities - Amortized Cost and Fair Value of Debt Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Securities available for sale, amortized cost, due in one year or less	$ 26,974
Securities available for sale, fair value, due in one year or less	26,899
Securities available for sale, amortized cost, due after one year through five years	45,469
Securities available for sale, fair value, due after one year through five years	46,060
Securities available for sale, amortized cost, due after five years through ten years	28,055
Securities available for sale, fair value, due after five years through ten years	29,166
Securities available for sale, amortized cost, due after ten years	32,788
Securities available for sale, fair value, due after ten years	34,450
Securities available for sale, amortized cost, single maturity	133,286
Securities available for sale, fair value, single maturity	136,575
Securities available for sale, amortized cost, Mortgage-backed securities and CMO	119,325
Securities available for sale, fair value, Mortgage-backed securities and CMO	118,453
Securities available for sale, fair value	255,028	$ 261,841
Debt Securities [Member]
Securities available for sale, amortized cost	252,611
Securities available for sale, fair value	$ 255,028

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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