Note 3 - Available for Sale Debt Securities - Securities With Unrealized Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Securities available-for-sale, less than 12 months, fair value	$ 27,372	$ 98,167
Securities available-for-sale, less than 12 months, unrealized losses	(97)	(603)
Securities available-for-sale, 12 months or more, fair value	1,480	43,945
Securities available-for-sale, 12 months or more, unrealized losses	(33)	(531)
Securities available-for-sale, fair value	28,852	142,112
Securities available-for-sale, unrealized losses	(130)	(1,134)
US Government-sponsored Enterprises Debt Securities [Member]
Securities available-for-sale, less than 12 months, fair value	26,339	16,503
Securities available-for-sale, less than 12 months, unrealized losses	(92)	(107)
Securities available-for-sale, 12 months or more, fair value	1,480	11,492
Securities available-for-sale, 12 months or more, unrealized losses	(33)	(71)
Securities available-for-sale, fair value	27,819	27,995
Securities available-for-sale, unrealized losses	(125)	(178)
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available-for-sale, less than 12 months, fair value	1,033	81,664
Securities available-for-sale, less than 12 months, unrealized losses	(5)	(496)
Securities available-for-sale, 12 months or more, fair value	0	32,453
Securities available-for-sale, 12 months or more, unrealized losses	0	(460)
Securities available-for-sale, fair value	1,033	114,117
Securities available-for-sale, unrealized losses	$ (5)	$ (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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