Note 2 - Securities Available for Sale - Amortized Cost and Fair Values of Securities Available for Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Securities available for sale, cost	$ 254,538	$ 246,579
Gross unrealized gains	1,092	1,878
Gross unrealized losses	(18,282)	(17,609)
Fair value	237,348	230,848
Collateralized Mortgage-Backed Securities [Member]
Securities available for sale, cost	10,596	11,350
Gross unrealized gains	2	13
Gross unrealized losses	(1,249)	(1,250)
Fair value	9,349	10,113
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Securities available for sale, cost	167,759	165,771
Gross unrealized gains	57	533
Gross unrealized losses	(15,194)	(13,995)
Fair value	152,622	152,309
Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Securities available for sale, cost	5,552	6,032
Gross unrealized gains	0	0
Gross unrealized losses	(525)	(513)
Fair value	5,027	5,519
Mortgage-related Securities [Member]
Securities available for sale, cost	183,907	183,153
Gross unrealized gains	59	546
Gross unrealized losses	(16,968)	(15,758)
Fair value	166,998	167,941
US States and Political Subdivisions Debt Securities [Member]
Securities available for sale, cost	60,631	53,426
Gross unrealized gains	1,033	1,332
Gross unrealized losses	(739)	(651)
Fair value	60,925	54,107
Other Debt Obligations [Member]
Securities available for sale, cost	10,000	10,000
Gross unrealized gains	0	0
Gross unrealized losses	(575)	(1,200)
Fair value	9,425	8,800
Debt Securities [Member]
Securities available for sale, cost	70,631	63,426
Debt [Member]
Gross unrealized gains	1,033	1,332
Gross unrealized losses	(1,314)	(1,851)
Fair value	$ 70,350	$ 62,907

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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