Note 2 - Securities - Unrealized Gross Losses and Fair Value of Securities in a Continuous Loss Position (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Securities available for sale, gross unrealized losses, less than twelve months	$ (485)	$ (640)
Securities available for sale, fair value, less than twelve months	30,799	61,358
Securities available for sale, gross unrealized losses, twelve months or longer	(2,505)	(2,316)
Securities available for sale, fair value, twelve months or longer	70,316	137,482
Securities available for sale, gross unrealized losses, total	(2,990)	(2,956)
Securities available for sale, fair value, total	101,115	198,840
US States and Political Subdivisions Debt Securities [Member]
Securities available for sale, gross unrealized losses, less than twelve months	(95)	(367)
Securities available for sale, fair value, less than twelve months	7,757	29,928
Securities available for sale, gross unrealized losses, twelve months or longer	0	0
Securities available for sale, fair value, twelve months or longer	0	0
Securities available for sale, gross unrealized losses, total	(95)	(367)
Securities available for sale, fair value, total	7,757	29,928
Asset-backed Securities, Issued by US Government Agencies [Member]
Securities available for sale, gross unrealized losses, less than twelve months	(172)	(59)
Securities available for sale, fair value, less than twelve months	8,172	3,855
Securities available for sale, gross unrealized losses, twelve months or longer	(1,248)	(879)
Securities available for sale, fair value, twelve months or longer	25,933	25,002
Securities available for sale, gross unrealized losses, total	(1,420)	(938)
Securities available for sale, fair value, total	34,105	28,857
Asset-backed Securities, Issued by Private Enterprises [Member]
Securities available for sale, gross unrealized losses, less than twelve months	(85)	(31)
Securities available for sale, fair value, less than twelve months	3,801	3,848
Securities available for sale, gross unrealized losses, twelve months or longer	(728)	(842)
Securities available for sale, fair value, twelve months or longer	26,982	37,007
Securities available for sale, gross unrealized losses, total	(813)	(873)
Securities available for sale, fair value, total	30,783	40,855
Corporate Debt Securities [Member]
Securities available for sale, gross unrealized losses, less than twelve months	(90)	(17)
Securities available for sale, fair value, less than twelve months	6,804	4,983
Securities available for sale, gross unrealized losses, twelve months or longer	(364)	(326)
Securities available for sale, fair value, twelve months or longer	9,622	4,660
Securities available for sale, gross unrealized losses, total	(454)	(343)
Securities available for sale, fair value, total	16,426	9,643
US Small Business Administration Securities [Member]
Securities available for sale, gross unrealized losses, less than twelve months	0	0
Securities available for sale, fair value, less than twelve months	65	0
Securities available for sale, gross unrealized losses, twelve months or longer	(1)	(36)
Securities available for sale, fair value, twelve months or longer	3,775	15,034
Securities available for sale, gross unrealized losses, total	(1)	(36)
Securities available for sale, fair value, total	3,840	15,034
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale, gross unrealized losses, less than twelve months	(12)	(166)
Securities available for sale, fair value, less than twelve months	2,221	18,744
Securities available for sale, gross unrealized losses, twelve months or longer	0	(175)
Securities available for sale, fair value, twelve months or longer	6	47,463
Securities available for sale, gross unrealized losses, total	(12)	(341)
Securities available for sale, fair value, total	2,227	66,207
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Securities available for sale, gross unrealized losses, less than twelve months	(31)	0
Securities available for sale, fair value, less than twelve months	1,979	0
Securities available for sale, gross unrealized losses, twelve months or longer	(164)	(58)
Securities available for sale, fair value, twelve months or longer	3,998	8,316
Securities available for sale, gross unrealized losses, total	(195)	(58)
Securities available for sale, fair value, total	$ 5,977	$ 8,316

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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