Note 3 - Securities - Securities in an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Available-for-sale securities, less than 12 months, fair value	$ 29,272	$ 45,014
Available-for-sale securities, less than 12 months, unrealized losses	(769)	(267)
Available-for-sale securities, 12 months or more, fair value	11,527	28,050
Available-for-sale securities, 12 months or more, unrealized losses	(126)	(321)
Available-for-sale securities, fair value	40,799	73,064
Available-for-sale securities, unrealized losses	(895)	(588)
US Government Agencies Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	4,061	6,473
Available-for-sale securities, less than 12 months, unrealized losses	(8)	(25)
Available-for-sale securities, 12 months or more, fair value	1,758	380
Available-for-sale securities, 12 months or more, unrealized losses	(11)	(2)
Available-for-sale securities, fair value	5,819	6,853
Available-for-sale securities, unrealized losses	(19)	(27)
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	3,125	2,249
Available-for-sale securities, less than 12 months, unrealized losses	(53)	(26)
Available-for-sale securities, 12 months or more, fair value
Available-for-sale securities, 12 months or more, unrealized losses
Available-for-sale securities, fair value	3,125	2,249
Available-for-sale securities, unrealized losses	(53)	(26)
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities, less than 12 months, fair value	17,165	31,817
Available-for-sale securities, less than 12 months, unrealized losses	(453)	(207)
Available-for-sale securities, 12 months or more, fair value	4,358	22,166
Available-for-sale securities, 12 months or more, unrealized losses	(88)	(235)
Available-for-sale securities, fair value	21,523	53,983
Available-for-sale securities, unrealized losses	(541)	(442)
Corporate Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value
Available-for-sale securities, less than 12 months, unrealized losses
Available-for-sale securities, 12 months or more, fair value	979	955
Available-for-sale securities, 12 months or more, unrealized losses	(21)	(45)
Available-for-sale securities, fair value	979	955
Available-for-sale securities, unrealized losses	(21)	(45)
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value		1,464
Available-for-sale securities, less than 12 months, unrealized losses		(1)
Available-for-sale securities, 12 months or more, fair value	4,432	4,549
Available-for-sale securities, 12 months or more, unrealized losses	(6)	(39)
Available-for-sale securities, fair value	4,432	6,013
Available-for-sale securities, unrealized losses	(6)	(40)
Asset-backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value	4,921	3,011
Available-for-sale securities, less than 12 months, unrealized losses	(255)	(8)
Available-for-sale securities, 12 months or more, fair value
Available-for-sale securities, 12 months or more, unrealized losses
Available-for-sale securities, fair value	4,921	3,011
Available-for-sale securities, unrealized losses	$ (255)	$ (8)

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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