Note 3 - Securities - Securities in an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Available-for-sale securities, less than 12 months, fair value	$ 8,378	$ 36,107
Available-for-sale securities, less than 12 months, unrealized losses	(59)	(269)
Available-for-sale securities, 12 months or more, fair value	142,360	144,730
Available-for-sale securities, 12 months or more, unrealized losses	(3,086)	(5,432)
Available-for-sale securities, fair value	150,738	180,837
Available-for-sale securities, unrealized losses	(3,145)	(5,701)
US Government Agencies Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	2,846	7,223
Available-for-sale securities, less than 12 months, unrealized losses	(21)	(39)
Available-for-sale securities, 12 months or more, fair value	13,045	12,274
Available-for-sale securities, 12 months or more, unrealized losses	(108)	(291)
Available-for-sale securities, fair value	15,891	19,497
Available-for-sale securities, unrealized losses	(129)	(330)
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	1,718	5,545
Available-for-sale securities, less than 12 months, unrealized losses	(18)	(40)
Available-for-sale securities, 12 months or more, fair value	10,347	16,320
Available-for-sale securities, 12 months or more, unrealized losses	(259)	(549)
Available-for-sale securities, fair value	12,065	21,865
Available-for-sale securities, unrealized losses	(277)	(589)
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities, less than 12 months, fair value	2,918	21,791
Available-for-sale securities, less than 12 months, unrealized losses	(12)	(183)
Available-for-sale securities, 12 months or more, fair value	95,998	93,038
Available-for-sale securities, 12 months or more, unrealized losses	(2,222)	(3,798)
Available-for-sale securities, fair value	98,916	114,829
Available-for-sale securities, unrealized losses	(2,234)	(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	2,958	2,922
Available-for-sale securities, 12 months or more, unrealized losses	(60)	(100)
Available-for-sale securities, fair value	2,958	2,922
Available-for-sale securities, unrealized losses	(60)	(100)
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value	896	1,548
Available-for-sale securities, less than 12 months, unrealized losses	(8)	(7)
Available-for-sale securities, 12 months or more, fair value	20,012	20,176
Available-for-sale securities, 12 months or more, unrealized losses	(437)	(694)
Available-for-sale securities, fair value	20,908	21,724
Available-for-sale securities, unrealized losses	$ (445)	$ (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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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