Note 3 - Available for Sale Debt Securities - Securities With Unrealized Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Securities available-for-sale, less than 12 months, fair value	$ 63,991	$ 98,167
Securities available-for-sale, less than 12 months, unrealized losses	(401)	(603)
Securities available-for-sale, 12 months or more, fair value	6,283	43,945
Securities available-for-sale, 12 months or more, unrealized losses	(66)	(531)
Securities available-for-sale, fair value	70,274	142,112
Securities available-for-sale, unrealized losses	(467)	(1,134)
US Government-sponsored Enterprises Debt Securities [Member]
Securities available-for-sale, less than 12 months, fair value	29,892	16,503
Securities available-for-sale, less than 12 months, unrealized losses	(314)	(107)
Securities available-for-sale, 12 months or more, fair value	5,289	11,492
Securities available-for-sale, 12 months or more, unrealized losses	(64)	(71)
Securities available-for-sale, fair value	35,181	27,995
Securities available-for-sale, unrealized losses	(378)	(178)
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available-for-sale, less than 12 months, fair value	34,099	81,664
Securities available-for-sale, less than 12 months, unrealized losses	(87)	(496)
Securities available-for-sale, 12 months or more, fair value	994	32,453
Securities available-for-sale, 12 months or more, unrealized losses	(2)	(460)
Securities available-for-sale, fair value	35,093	114,117
Securities available-for-sale, unrealized losses	$ (89)	$ (956)

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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