Note 3 - Securities - Securities in an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Available-for-sale securities, less than 12 months, fair value	$ 28,644	$ 45,014
Available-for-sale securities, less than 12 months, unrealized losses	(250)	(267)
Available-for-sale securities, 12 months or more, fair value	3,121	28,050
Available-for-sale securities, 12 months or more, unrealized losses	(16)	(321)
Available-for-sale securities, fair value	31,765	73,064
Available-for-sale securities, unrealized losses	(266)	(588)
US Government Agencies Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	0	6,473
Available-for-sale securities, less than 12 months, unrealized losses	0	(25)
Available-for-sale securities, 12 months or more, fair value	2,836	380
Available-for-sale securities, 12 months or more, unrealized losses	(10)	(2)
Available-for-sale securities, fair value	2,836	6,853
Available-for-sale securities, unrealized losses	(10)	(27)
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	5,915	2,249
Available-for-sale securities, less than 12 months, unrealized losses	(46)	(26)
Available-for-sale securities, 12 months or more, fair value	0	0
Available-for-sale securities, 12 months or more, unrealized losses	0	0
Available-for-sale securities, fair value	5,915	2,249
Available-for-sale securities, unrealized losses	(46)	(26)
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities, less than 12 months, fair value	17,671	31,817
Available-for-sale securities, less than 12 months, unrealized losses	(159)	(207)
Available-for-sale securities, 12 months or more, fair value	285	22,166
Available-for-sale securities, 12 months or more, unrealized losses	(6)	(235)
Available-for-sale securities, fair value	17,956	53,983
Available-for-sale securities, unrealized losses	(165)	(442)
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value	2,057	1,464
Available-for-sale securities, less than 12 months, unrealized losses	(8)	(1)
Available-for-sale securities, 12 months or more, fair value	0	4,549
Available-for-sale securities, 12 months or more, unrealized losses	0	(39)
Available-for-sale securities, fair value	2,057	6,013
Available-for-sale securities, unrealized losses	(8)	(40)
Corporate Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value		0
Available-for-sale securities, less than 12 months, unrealized losses		0
Available-for-sale securities, 12 months or more, fair value		955
Available-for-sale securities, 12 months or more, unrealized losses		(45)
Available-for-sale securities, fair value		955
Available-for-sale securities, unrealized losses		(45)
Asset-backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value	3,001	3,011
Available-for-sale securities, less than 12 months, unrealized losses	(37)	(8)
Available-for-sale securities, 12 months or more, fair value	0	0
Available-for-sale securities, 12 months or more, unrealized losses	0	0
Available-for-sale securities, fair value	3,001	3,011
Available-for-sale securities, unrealized losses	$ (37)	$ (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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