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Note 2 - Investments - Schedule of Amortized Costs and Fair Values of Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023
Amortized cost, available for sale securities	$ 316,735	$ 310,272
Gross unrealized gains, available for sale securities	1,582	471
Gross unrealized losses, available for sale securities	(27,184)	(29,568)
Total securities available-for-sale, fair value	291,133	281,175
Available-for-Sale, Allowance for Credit Loss	0	0
Amortized cost, held to maturity securities	10,500	8,500
Gross unrealized gains, held to maturity securities	1	0
Gross unrealized losses, held to maturity securities	(243)	(356)
Securities held-to-maturity, at fair value	10,258	8,144
Securities held-to-maturity	66	45	$ 45	$ 45
Amortized cost, available for sale and held to maturity securities	327,235	318,772
Gross unrealized gains, available for sale and held to maturity securities	1,583	471
Gross unrealized losses, available for sale and held to maturity securities	(27,427)	(29,924)
Total securities, fair value	301,391	289,319
ACL, available for sale and held to maturity securities	66	45
US Government Agencies Debt Securities [Member]
Amortized cost, available for sale securities	20,251	20,247
Gross unrealized gains, available for sale securities	45	45
Gross unrealized losses, available for sale securities	(2,728)	(3,154)
Total securities available-for-sale, fair value	17,568	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	8	8
Gross unrealized losses, available for sale securities	(821)	(882)
Total securities available-for-sale, fair value	15,187	15,126
Available-for-Sale, Allowance for Credit Loss	0	0
Amortized cost, held to maturity securities	10,500	8,500
Gross unrealized gains, held to maturity securities	1	0
Gross unrealized losses, held to maturity securities	(243)	(356)
Securities held-to-maturity, at fair value	10,258	8,144
Securities held-to-maturity	66	45
Municipal Bonds [Member]
Amortized cost, available for sale securities	82,495	82,774
Gross unrealized gains, available for sale securities	0	0
Gross unrealized losses, available for sale securities	(12,374)	(12,430)
Total securities available-for-sale, fair value	70,121	70,344
Available-for-Sale, Allowance for Credit Loss	0	0
Collateralized Mortgage-Backed Securities [Member]
Amortized cost, available for sale securities	186,222	178,740
Gross unrealized gains, available for sale securities	1,462	415
Gross unrealized losses, available for sale securities	(10,302)	(11,969)
Total securities available-for-sale, fair value	177,382	167,186
Available-for-Sale, Allowance for Credit Loss	0	0
Asset-Backed Securities [Member]
Amortized cost, available for sale securities	11,767	12,511
Gross unrealized gains, available for sale securities	67	3
Gross unrealized losses, available for sale securities	(959)	(1,133)
Total securities available-for-sale, fair value	10,875	11,381
Available-for-Sale, Allowance for Credit Loss	$ 0	$ 0

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