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Note 2 - Investments - Schedule 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	$ 335,152		$ 310,272
Gross unrealized gains, available for sale securities	908		471
Gross unrealized losses, available for sale securities	(24,365)		(29,568)
Total securities available-for-sale, fair value	311,695		281,175
Available-for-Sale, Allowance for Credit Loss	0		0
Amortized cost, held to maturity securities	31,606		8,500
Gross unrealized gains, held to maturity securities	618		0
Gross unrealized losses, held to maturity securities	(82)		(356)
Securities held-to-maturity, at fair value	32,142		8,144
Securities held-to-maturity, ACL	220	$ 220	45	$ 45	$ 45	$ 45
Amortized cost, available for sale and held to maturity securities	366,758		318,772
Gross unrealized gains, available for sale and held to maturity securities	1,526		471
Gross unrealized losses, available for sale and held to maturity securities	(24,447)		(29,924)
Total securities, fair value	343,837		289,319
ACL, available for sale and held to maturity securities	220		45
US Government Agencies Debt Securities [Member]
Amortized cost, available for sale securities	20,260		20,247
Gross unrealized gains, available for sale securities	31		45
Gross unrealized losses, available for sale securities	(2,303)		(3,154)
Total securities available-for-sale, fair value	17,988		17,138
Available-for-Sale, Allowance for Credit Loss	0		0
Corporate Debt Securities [Member]
Amortized cost, available for sale securities	16,000		16,000
Gross unrealized gains, available for sale securities	7		8
Gross unrealized losses, available for sale securities	(556)		(882)
Total securities available-for-sale, fair value	15,451		15,126
Available-for-Sale, Allowance for Credit Loss	0		0
Amortized cost, held to maturity securities	29,336		8,500
Gross unrealized gains, held to maturity securities	404		0
Gross unrealized losses, held to maturity securities	(82)		(356)
Securities held-to-maturity, at fair value	29,658		8,144
Securities held-to-maturity, ACL	220		45
Municipal Bonds [Member]
Amortized cost, available for sale securities	81,925		82,774
Gross unrealized gains, available for sale securities	5		0
Gross unrealized losses, available for sale securities	(11,225)		(12,430)
Total securities available-for-sale, fair value	70,705		70,344
Available-for-Sale, Allowance for Credit Loss	0		0
Amortized cost, held to maturity securities	2,270
Gross unrealized gains, held to maturity securities	214
Gross unrealized losses, held to maturity securities	0
Securities held-to-maturity, at fair value	2,484
Securities held-to-maturity, ACL	0
Collateralized Mortgage-Backed Securities [Member]
Amortized cost, available for sale securities	205,937		178,740
Gross unrealized gains, available for sale securities	865		415
Gross unrealized losses, available for sale securities	(9,580)		(11,969)
Total securities available-for-sale, fair value	197,222		167,186
Available-for-Sale, Allowance for Credit Loss	0		0
Asset-Backed Securities [Member]
Amortized cost, available for sale securities	11,030		12,511
Gross unrealized gains, available for sale securities	0		3
Gross unrealized losses, available for sale securities	(701)		(1,133)
Total securities available-for-sale, fair value	10,329		11,381
Available-for-Sale, Allowance for Credit Loss	$ 0		$ 0

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