Note 2 - Securities - Unrealized Gross Losses and Fair Value of Securities in a Continuous Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Securities available for sale, gross unrealized losses, less than twelve months	$ (201)	$ (653)
Securities available for sale, fair value, less than twelve months	16,696	41,933
Securities available for sale, gross unrealized losses, twelve months or longer	(32,924)	(35,506)
Securities available for sale, fair value, twelve months or longer	219,458	241,991
Securities available for sale, gross unrealized losses, total	(33,125)	(36,159)
Securities available for sale, fair value, total	236,154	283,924
US States and Political Subdivisions Debt Securities [Member]
Securities available for sale, gross unrealized losses, less than twelve months	0	0
Securities available for sale, fair value, less than twelve months	0	0
Securities available for sale, gross unrealized losses, twelve months or longer	(15,476)	(15,336)
Securities available for sale, fair value, twelve months or longer	77,324	77,876
Securities available for sale, gross unrealized losses, total	(15,476)	(15,336)
Securities available for sale, fair value, total	77,324	77,876
US Government Agencies Debt Securities [Member]
Securities available for sale, gross unrealized losses, less than twelve months	(3)	(21)
Securities available for sale, fair value, less than twelve months	3,243	2,957
Securities available for sale, gross unrealized losses, twelve months or longer	(107)	(63)
Securities available for sale, fair value, twelve months or longer	9,055	6,311
Securities available for sale, gross unrealized losses, total	(110)	(84)
Securities available for sale, fair value, total	12,298	9,268
Corporate Issued Asset-backed Securities [Member]
Securities available for sale, gross unrealized losses, less than twelve months	(1)	0
Securities available for sale, fair value, less than twelve months	1,510	0
Securities available for sale, gross unrealized losses, twelve months or longer	(4)	(5)
Securities available for sale, fair value, twelve months or longer	1,555	2,798
Securities available for sale, gross unrealized losses, total	(5)	(5)
Securities available for sale, fair value, total	3,065	2,798
Corporate Debt Securities [Member]
Securities available for sale, gross unrealized losses, less than twelve months	0	0
Securities available for sale, fair value, less than twelve months	0	0
Securities available for sale, gross unrealized losses, twelve months or longer	(2,674)	(3,670)
Securities available for sale, fair value, twelve months or longer	41,285	46,355
Securities available for sale, gross unrealized losses, total	(2,674)	(3,670)
Securities available for sale, fair value, total	41,285	46,355
US Small Business Administration Securities [Member]
Securities available for sale, gross unrealized losses, less than twelve months	0	(16)
Securities available for sale, fair value, less than twelve months	0	3,093
Securities available for sale, gross unrealized losses, twelve months or longer	(10)	0
Securities available for sale, fair value, twelve months or longer	901	0
Securities available for sale, gross unrealized losses, total	(10)	(16)
Securities available for sale, fair value, total	901	3,093
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Securities available for sale, gross unrealized losses, less than twelve months	(161)	(545)
Securities available for sale, fair value, less than twelve months	7,613	26,531
Securities available for sale, gross unrealized losses, twelve months or longer	(11,214)	(12,213)
Securities available for sale, fair value, twelve months or longer	55,175	51,181
Securities available for sale, gross unrealized losses, total	(11,375)	(12,758)
Securities available for sale, fair value, total	62,788	77,712
Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Securities available for sale, gross unrealized losses, less than twelve months	(36)	(71)
Securities available for sale, fair value, less than twelve months	4,330	9,352
Securities available for sale, gross unrealized losses, twelve months or longer	(3,439)	(4,219)
Securities available for sale, fair value, twelve months or longer	34,163	57,470
Securities available for sale, gross unrealized losses, total	(3,475)	(4,290)
Securities available for sale, fair value, total	$ 38,493	$ 66,822

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.

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