Note 4 - Securities - Securities in an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available-for-sale securities, less than 12 months, fair value	$ 45,014	$ 36,107
Available-for-sale securities, less than 12 months, unrealized losses	(267)	(269)
Available-for-sale securities, 12 months or more, fair value	28,050	144,730
Available-for-sale securities, 12 months or more, unrealized losses	(321)	(5,432)
Available-for-sale securities, fair value	73,064	180,837
Available-for-sale securities, unrealized losses	(588)	(5,701)
US Government Agencies Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	6,473	7,223
Available-for-sale securities, less than 12 months, unrealized losses	(25)	(39)
Available-for-sale securities, 12 months or more, fair value	380	12,274
Available-for-sale securities, 12 months or more, unrealized losses	(2)	(291)
Available-for-sale securities, fair value	6,853	19,497
Available-for-sale securities, unrealized losses	(27)	(330)
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	2,249	5,545
Available-for-sale securities, less than 12 months, unrealized losses	(26)	(40)
Available-for-sale securities, 12 months or more, fair value		16,320
Available-for-sale securities, 12 months or more, unrealized losses		(549)
Available-for-sale securities, fair value	2,249	21,865
Available-for-sale securities, unrealized losses	(26)	(589)
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities, less than 12 months, fair value	31,817	21,791
Available-for-sale securities, less than 12 months, unrealized losses	(207)	(183)
Available-for-sale securities, 12 months or more, fair value	22,166	93,038
Available-for-sale securities, 12 months or more, unrealized losses	(235)	(3,798)
Available-for-sale securities, fair value	53,983	114,829
Available-for-sale securities, unrealized losses	(442)	(3,981)
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	955	2,922
Available-for-sale securities, 12 months or more, unrealized losses	(45)	(100)
Available-for-sale securities, fair value	955	2,922
Available-for-sale securities, unrealized losses	(45)	(100)
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value	1,464	1,548
Available-for-sale securities, less than 12 months, unrealized losses	(1)	(7)
Available-for-sale securities, 12 months or more, fair value	4,549	20,176
Available-for-sale securities, 12 months or more, unrealized losses	(39)	(694)
Available-for-sale securities, fair value	6,013	21,724
Available-for-sale securities, unrealized losses	(40)	$ (701)
Asset-backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value	3,011
Available-for-sale securities, less than 12 months, unrealized losses	(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	3,011
Available-for-sale securities, unrealized losses	$ (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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