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Note 3 - Investments - Schedule of Amortized Costs and Fair Values of Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Amortized cost, available for sale securities	$ 310,272	$ 328,695
Gross unrealized gains, available for sale securities	471	939
Gross unrealized losses, available for sale securities	(29,568)	(36,701)
Total securities available-for-sale, fair value	281,175	292,933
Available-for-Sale, Allowance for Credit Loss	0	0
Amortized cost, held to maturity securities	8,500	8,500
Gross unrealized gains, held to maturity securities	0	0
Gross unrealized losses, held to maturity securities	(356)	(834)
Securities held-to-maturity, at fair value	8,144	7,666
Securities available for sale, HTM, ACL	45	45	$ 31	$ 0
Amortized cost, available for sale and held to maturity securities	318,772	337,195
Gross unrealized gains, available for sale and held to maturity securities	471	939
Gross unrealized losses, available for sale and held to maturity securities	(29,924)	(37,535)
Total securities, fair value	289,319	300,599
ACL, available for sale and held to maturity securities	45	45
US Government Agencies Debt Securities [Member]
Amortized cost, available for sale securities	20,247	21,151
Gross unrealized gains, available for sale securities	45	46
Gross unrealized losses, available for sale securities	(3,154)	(3,179)
Total securities available-for-sale, fair value	17,138	18,018
Available-for-Sale, Allowance for Credit Loss	0	0
Corporate Debt Securities [Member]
Amortized cost, available for sale securities	16,000	13,000
Gross unrealized gains, available for sale securities	8	613
Gross unrealized losses, available for sale securities	(882)	(741)
Total securities available-for-sale, fair value	15,126	12,872
Available-for-Sale, Allowance for Credit Loss	0	0
Amortized cost, held to maturity securities	8,500	8,500
Gross unrealized gains, held to maturity securities	0	0
Gross unrealized losses, held to maturity securities	(356)	(834)
Securities held-to-maturity, at fair value	8,144	7,666
Securities available for sale, HTM, ACL	45	45
Municipal Bonds [Member]
Amortized cost, available for sale securities	82,774	138,803
Gross unrealized gains, available for sale securities	0	42
Gross unrealized losses, available for sale securities	(12,430)	(19,398)
Total securities available-for-sale, fair value	70,344	119,447
Available-for-Sale, Allowance for Credit Loss	0	0
Collateralized Mortgage-Backed Securities [Member]
Amortized cost, available for sale securities	178,740	112,855
Gross unrealized gains, available for sale securities	415	238
Gross unrealized losses, available for sale securities	(11,969)	(11,845)
Total securities available-for-sale, fair value	167,186	101,248
Available-for-Sale, Allowance for Credit Loss	0	0
Asset-Backed Securities [Member]
Amortized cost, available for sale securities	12,511	42,886
Gross unrealized gains, available for sale securities	3	0
Gross unrealized losses, available for sale securities	(1,133)	(1,538)
Total securities available-for-sale, fair value	11,381	41,348
Available-for-Sale, Allowance for Credit Loss	$ 0	$ 0

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