Note 3 - Securities - Securities in an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Available-for-sale securities, less than 12 months, fair value	$ 55,782	$ 36,107
Available-for-sale securities, less than 12 months, unrealized losses	(410)	(269)
Available-for-sale securities, 12 months or more, fair value	38,295	144,730
Available-for-sale securities, 12 months or more, unrealized losses	(590)	(5,432)
Available-for-sale securities, fair value	94,077	180,837
Available-for-sale securities, unrealized losses	(1,000)	(5,701)
US Government Agencies Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	4,233	7,223
Available-for-sale securities, less than 12 months, unrealized losses	(16)	(39)
Available-for-sale securities, 12 months or more, fair value	415	12,274
Available-for-sale securities, 12 months or more, unrealized losses	(2)	(291)
Available-for-sale securities, fair value	4,648	19,497
Available-for-sale securities, unrealized losses	(18)	(330)
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	1,728	5,545
Available-for-sale securities, less than 12 months, unrealized losses	(24)	(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	1,728	21,865
Available-for-sale securities, unrealized losses	(24)	(589)
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities, less than 12 months, fair value	47,359	21,791
Available-for-sale securities, less than 12 months, unrealized losses	(350)	(183)
Available-for-sale securities, 12 months or more, fair value	32,173	93,038
Available-for-sale securities, 12 months or more, unrealized losses	(514)	(3,798)
Available-for-sale securities, fair value	79,532	114,829
Available-for-sale securities, unrealized losses	(864)	(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	978	2,922
Available-for-sale securities, 12 months or more, unrealized losses	(22)	(100)
Available-for-sale securities, fair value	978	2,922
Available-for-sale securities, unrealized losses	(22)	(100)
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value	2,462	1,548
Available-for-sale securities, less than 12 months, unrealized losses	(20)	(7)
Available-for-sale securities, 12 months or more, fair value	4,729	20,176
Available-for-sale securities, 12 months or more, unrealized losses	(52)	(694)
Available-for-sale securities, fair value	7,191	21,724
Available-for-sale securities, unrealized losses	$ (72)	$ (701)

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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-Publisher FASB
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