Note 3 - Securities - Securities in an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Available-for-sale securities, less than 12 months, fair value	$ 8,682	$ 36,107
Available-for-sale securities, less than 12 months, unrealized losses	(34)	(269)
Available-for-sale securities, 12 months or more, fair value	71,905	144,730
Available-for-sale securities, 12 months or more, unrealized losses	(848)	(5,432)
Available-for-sale securities, fair value	80,587	180,837
Available-for-sale securities, unrealized losses	(882)	(5,701)
US Government Agencies Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	3,462	7,223
Available-for-sale securities, less than 12 months, unrealized losses	(22)	(39)
Available-for-sale securities, 12 months or more, fair value	1,958	12,274
Available-for-sale securities, 12 months or more, unrealized losses	(6)	(291)
Available-for-sale securities, fair value	5,420	19,497
Available-for-sale securities, unrealized losses	(28)	(330)
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	409	5,545
Available-for-sale securities, less than 12 months, unrealized losses	(1)	(40)
Available-for-sale securities, 12 months or more, fair value	2,070	16,320
Available-for-sale securities, 12 months or more, unrealized losses	(15)	(549)
Available-for-sale securities, fair value	2,479	21,865
Available-for-sale securities, unrealized losses	(16)	(589)
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities, less than 12 months, fair value	4,811	21,791
Available-for-sale securities, less than 12 months, unrealized losses	(11)	(183)
Available-for-sale securities, 12 months or more, fair value	56,087	93,038
Available-for-sale securities, 12 months or more, unrealized losses	(655)	(3,798)
Available-for-sale securities, fair value	60,898	114,829
Available-for-sale securities, unrealized losses	(666)	(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	2,978	2,922
Available-for-sale securities, 12 months or more, unrealized losses	(36)	(100)
Available-for-sale securities, fair value	2,978	2,922
Available-for-sale securities, unrealized losses	(36)	(100)
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value		1,548
Available-for-sale securities, less than 12 months, unrealized losses		(7)
Available-for-sale securities, 12 months or more, fair value	8,812	20,176
Available-for-sale securities, 12 months or more, unrealized losses	(136)	(694)
Available-for-sale securities, fair value	8,812	21,724
Available-for-sale securities, unrealized losses	$ (136)	$ (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
-Topic 326
-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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