Note 2 - Investment Securities - Investment Securities in a Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Available for sale debt securities, continuous unrealized loss position less than 12 months, fair value	$ 22,308	$ 27,655
Available for sale debt securities, continuous unrealized loss position less than 12 months, gross unrealized losses	(831)	(458)
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, fair value	230,703	240,739
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross unrealized losses	(23,705)	(27,092)
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	1,815	1,749
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross unrealized losses	(115)	(188)
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	44,422	46,914
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross unrealized losses	(4,210)	(5,679)
US States and Political Subdivisions Debt Securities [Member]
Available for sale debt securities, continuous unrealized loss position less than 12 months, fair value	12,079	14,678
Available for sale debt securities, continuous unrealized loss position less than 12 months, gross unrealized losses	(725)	(261)
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, fair value	102,187	102,521
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross unrealized losses	(12,641)	(12,972)
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	3,148	4,163
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross unrealized losses	(102)	(87)
Mortgage-backed Securities and Collateralized Mortgage Obligations [Member]
Available for sale debt securities, continuous unrealized loss position less than 12 months, fair value	10,229	10,984
Available for sale debt securities, continuous unrealized loss position less than 12 months, gross unrealized losses	(106)	(188)
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, fair value	78,931	85,392
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross unrealized losses	(6,637)	(8,166)
Asset-Backed Securities [Member]
Available for sale debt securities, continuous unrealized loss position less than 12 months, fair value	0	1,993
Available for sale debt securities, continuous unrealized loss position less than 12 months, gross unrealized losses	0	(9)
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, fair value	200	0
Available for sale debt securities, continuous unrealized loss position for 12 months or longer, gross unrealized losses	$ 0	$ 0

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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