Note 3 - Debt Securities - Available For Sale Securities in Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Securities available for sale, less than 12 months, fair value	$ 8,995	$ 42,838
Securities available for sale, less than 12 months, unrealized losses	(52)	(171)
Securities available for sale, 12 months or longer, fair value	8,319	33,425
Securities available for sale, 12 months or longer, unrealized losses	(118)	(1,121)
Securities available for sale, total fair value	17,314	76,263
Securities available for sale, total unrealized losses	(170)	(1,292)
US Government Agencies Debt Securities [Member]
Securities available for sale, less than 12 months, fair value	975
Securities available for sale, less than 12 months, unrealized losses	(4)
Securities available for sale, 12 months or longer, fair value
Securities available for sale, 12 months or longer, unrealized losses
Securities available for sale, total fair value	975
Securities available for sale, total unrealized losses	(4)
US Treasury Securities [Member]
Securities available for sale, less than 12 months, fair value		19,960
Securities available for sale, less than 12 months, unrealized losses		(10)
Securities available for sale, 12 months or longer, fair value
Securities available for sale, 12 months or longer, unrealized losses
Securities available for sale, total fair value		19,960
Securities available for sale, total unrealized losses		(10)
US States and Political Subdivisions Debt Securities [Member]
Securities available for sale, less than 12 months, fair value		7,116
Securities available for sale, less than 12 months, unrealized losses		(62)
Securities available for sale, 12 months or longer, fair value		18,081
Securities available for sale, 12 months or longer, unrealized losses		(447)
Securities available for sale, total fair value		25,197
Securities available for sale, total unrealized losses		(509)
Mortgage-backed Agency Securities [Member]
Securities available for sale, less than 12 months, fair value	8,020	15,762
Securities available for sale, less than 12 months, unrealized losses	(48)	(99)
Securities available for sale, 12 months or longer, fair value	8,319	15,344
Securities available for sale, 12 months or longer, unrealized losses	(118)	(674)
Securities available for sale, total fair value	16,339	31,106
Securities available for sale, total unrealized losses	$ (166)	$ (773)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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