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Note 2 - Securities - Summary of Amortized Costs and Fair Values of Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Amortized cost, available for sale securities	$ 211,918		$ 185,917
Gross unrealized gains, available for sale securities	360		62
Gross unrealized losses, available for sale securities	(15,802)		(22,132)
Fair value, available for sale securities	196,476		163,847
Securities available for sale, AFS	0		0
Amortized cost, held to maturity	104,691		109,836
Gross unrealized gains, held to maturity securities	29		8
Gross unrealized losses, held to maturity securities	(7,345)		(10,969)
Fair value, held to maturity securities	97,375		98,875
Securities available for sale, HTM	(83)	$ (98)	(95)	$ (104)	$ (109)	$ (107)
Amortized cost, , available for sale and held to maturity securities	316,609		295,753
Gross unrealized gains, available for sale and held to maturity securities	389		70
Gross unrealized losses	(23,147)		(33,101)
Fair value, available for sale and held to maturity securities	293,851		262,722
Securities available for sale, available for sale and HTM	(83)		(95)
US Treasury Securities [Member]
Amortized cost, available for sale securities	34,425		12,483
Gross unrealized gains, available for sale securities	124		0
Gross unrealized losses, available for sale securities	(418)		(795)
Fair value, available for sale securities	34,131		11,688
Securities available for sale, AFS	0		0
Amortized cost, held to maturity	9,825		9,632
Gross unrealized gains, held to maturity securities	0		0
Gross unrealized losses, held to maturity securities	(31)		(125)
Fair value, held to maturity securities	9,794		9,507
Securities available for sale, HTM	0	0	0	0	0	0
US Agency and Mortgage-backed Securities [Member]
Amortized cost, available for sale securities	115,347		110,480
Gross unrealized gains, available for sale securities	206		57
Gross unrealized losses, available for sale securities	(8,911)		(12,498)
Fair value, available for sale securities	106,642		98,039
Securities available for sale, AFS	0		0
Amortized cost, held to maturity	81,431		86,555
Gross unrealized gains, held to maturity securities	7		0
Gross unrealized losses, held to maturity securities	(6,178)		(9,282)
Fair value, held to maturity securities	75,260		77,273
Securities available for sale, HTM	0	0	0	0	0	0
US States and Political Subdivisions Debt Securities [Member]
Amortized cost, available for sale securities	62,146		62,954
Gross unrealized gains, available for sale securities	30		5
Gross unrealized losses, available for sale securities	(6,473)		(8,839)
Fair value, available for sale securities	55,703		54,120
Securities available for sale, AFS	0		0
Amortized cost, held to maturity	10,435		10,649
Gross unrealized gains, held to maturity securities	22		8
Gross unrealized losses, held to maturity securities	(828)		(1,112)
Fair value, held to maturity securities	9,629		9,545
Securities available for sale, HTM	0	0	0	(1)	(1)	0
Corporate Debt Securities [Member]
Amortized cost, held to maturity	3,000		3,000
Gross unrealized gains, held to maturity securities	0		0
Gross unrealized losses, held to maturity securities	(308)		(450)
Fair value, held to maturity securities	2,692		2,550
Securities available for sale, HTM	$ (83)	$ (98)	$ (95)	$ (103)	$ (108)	$ (107)

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Amount of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity) and 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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