Note 2 - Investment Securities - Investment Securities in a Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Available for sale debt securities, continuous unrealized loss position less than 12 months, fair value	$ 30,074	$ 10,211
Available for sale debt securities, continuous unrealized loss position less than 12 months, gross unrealized losses	(638)	(143)
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, fair value	216,360	229,580
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross unrealized losses	(19,855)	(17,731)
US Government Agencies Debt Securities [Member]
Available for sale debt securities, continuous unrealized loss position less than 12 months, fair value	0	0
Available for sale debt securities, continuous unrealized loss position less than 12 months, gross unrealized losses	0	0
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, fair value	1,811	1,848
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross unrealized losses	(116)	(86)
US Treasury and Government [Member]
Available for sale debt securities, continuous unrealized loss position less than 12 months, fair value	0	0
Available for sale debt securities, continuous unrealized loss position less than 12 months, gross unrealized losses	0	0
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, fair value	43,926	44,308
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross unrealized losses	(3,749)	(3,357)
US States and Political Subdivisions Debt Securities [Member]
Available for sale debt securities, continuous unrealized loss position less than 12 months, fair value	17,226	4,250
Available for sale debt securities, continuous unrealized loss position less than 12 months, gross unrealized losses	(541)	(101)
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, fair value	97,723	107,365
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross unrealized losses	(10,285)	(9,097)
Corporate Debt Securities [Member]
Available for sale debt securities, continuous unrealized loss position less than 12 months, fair value	0	0
Available for sale debt securities, continuous unrealized loss position less than 12 months, gross unrealized losses	0	0
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, fair value	1,970	1,971
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross unrealized losses	(30)	(29)
Mortgage-backed Securities and Collateralized Mortgage Obligations [Member]
Available for sale debt securities, continuous unrealized loss position less than 12 months, fair value	11,492	5,961
Available for sale debt securities, continuous unrealized loss position less than 12 months, gross unrealized losses	(97)	(42)
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, fair value	70,783	73,924
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross unrealized losses	(5,674)	(5,161)
Asset-Backed Securities [Member]
Available for sale debt securities, continuous unrealized loss position less than 12 months, fair value	1,356	0
Available for sale debt securities, continuous unrealized loss position less than 12 months, gross unrealized losses	0	0
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, fair value	147	164
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross 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/exampleRef
-Topic 326
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