Note 3 - Securities - Securities in an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Available-for-sale securities, less than 12 months, fair value	$ 253,028	$ 83,309
Available-for-sale securities, less than 12 months, unrealized losses	(2,912)	(288)
Available-for-sale securities, 12 months or more, fair value	569	2,794
Available-for-sale securities, 12 months or more, unrealized losses	(7)	(14)
Available-for-sale securities, fair value	253,597	86,103
Available-for-sale securities, unrealized losses	(2,919)	(302)
US Government Agencies Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	2,920	0
Available-for-sale securities, less than 12 months, unrealized losses	(32)	0
Available-for-sale securities, 12 months or more, fair value	286	1,615
Available-for-sale securities, 12 months or more, unrealized losses	(2)	(8)
Available-for-sale securities, fair value	3,206	1,615
Available-for-sale securities, unrealized losses	(34)	(8)
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	36,685	7,291
Available-for-sale securities, less than 12 months, unrealized losses	(574)	(29)
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	36,685	7,291
Available-for-sale securities, unrealized losses	(574)	(29)
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities, less than 12 months, fair value	185,745	68,512
Available-for-sale securities, less than 12 months, unrealized losses	(2,007)	(241)
Available-for-sale securities, 12 months or more, fair value	283	249
Available-for-sale securities, 12 months or more, unrealized losses	(5)	(5)
Available-for-sale securities, fair value	186,028	68,761
Available-for-sale securities, unrealized losses	(2,012)	(246)
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value	25,891	5,400
Available-for-sale securities, less than 12 months, unrealized losses	(298)	(18)
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	25,891	5,400
Available-for-sale securities, unrealized losses	(298)	(18)
Asset-backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value	1,787	2,106
Available-for-sale securities, less than 12 months, unrealized losses	(1)	0
Available-for-sale securities, 12 months or more, fair value	0	930
Available-for-sale securities, 12 months or more, unrealized losses	0	(1)
Available-for-sale securities, fair value	1,787	3,036
Available-for-sale securities, unrealized losses	$ (1)	$ (1)

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
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922890-210455

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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