Note 3 - Securities - Securities in an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Available-for-sale securities, less than 12 months, fair value	$ 13,499	$ 45,014
Available-for-sale securities, less than 12 months, unrealized losses	(218)	(267)
Available-for-sale securities, 12 months or more, fair value	3,066	28,050
Available-for-sale securities, 12 months or more, unrealized losses	(19)	(321)
Available-for-sale securities, fair value	16,565	73,064
Available-for-sale securities, unrealized losses	(237)	(588)
US Government Agencies Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	1,232	6,473
Available-for-sale securities, less than 12 months, unrealized losses	(2)	(25)
Available-for-sale securities, 12 months or more, fair value	2,773	380
Available-for-sale securities, 12 months or more, unrealized losses	(14)	(2)
Available-for-sale securities, fair value	4,005	6,853
Available-for-sale securities, unrealized losses	(16)	(27)
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	3,444	2,249
Available-for-sale securities, less than 12 months, unrealized losses	(25)	(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	3,444	2,249
Available-for-sale securities, unrealized losses	(25)	(26)
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities, less than 12 months, fair value	2,590	31,817
Available-for-sale securities, less than 12 months, unrealized losses	(37)	(207)
Available-for-sale securities, 12 months or more, fair value	293	22,166
Available-for-sale securities, 12 months or more, unrealized losses	(5)	(235)
Available-for-sale securities, fair value	2,883	53,983
Available-for-sale securities, unrealized losses	(42)	(442)
Asset-backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value	6,233	3,011
Available-for-sale securities, less than 12 months, unrealized losses	(154)	(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	6,233	3,011
Available-for-sale securities, unrealized losses	$ (154)	(8)
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)
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value		1,464
Available-for-sale securities, less than 12 months, unrealized losses		(1)
Available-for-sale securities, 12 months or more, fair value		4,549
Available-for-sale securities, 12 months or more, unrealized losses		(39)
Available-for-sale securities, fair value		6,013
Available-for-sale securities, unrealized losses		$ (40)

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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