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Note 2 - Investments - Schedule of Amortized Costs and Fair Values of Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Amortized cost, available for sale securities	$ 329,830		$ 310,272
Gross unrealized gains, available for sale securities	1,079		471
Gross unrealized losses, available for sale securities	(28,217)		(29,568)
Total securities available-for-sale, fair value	302,692		281,175
Available-for-Sale, Allowance for Credit Loss	0		0
Amortized cost, held to maturity securities	31,782		8,500
Gross unrealized gains, held to maturity securities	302		0
Gross unrealized losses, held to maturity securities	(308)		(356)
Securities held-to-maturity, at fair value	31,776		8,144
Securities held-to-maturity, ACL	220	$ 66	45	$ 45	$ 45	$ 45
Amortized cost, available for sale and held to maturity securities	361,612		318,772
Gross unrealized gains, available for sale and held to maturity securities	1,381		471
Gross unrealized losses, available for sale and held to maturity securities	(28,525)		(29,924)
Total securities, fair value	334,468		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	20,255		20,247
Gross unrealized gains, available for sale securities	33		45
Gross unrealized losses, available for sale securities	(2,593)		(3,154)
Total securities available-for-sale, fair value	17,695		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	11		8
Gross unrealized losses, available for sale securities	(652)		(882)
Total securities available-for-sale, fair value	15,359		15,126
Available-for-Sale, Allowance for Credit Loss	0		0
Amortized cost, held to maturity securities	29,525		8,500
Gross unrealized gains, held to maturity securities	302		0
Gross unrealized losses, held to maturity securities	(303)		(356)
Securities held-to-maturity, at fair value	29,524		8,144
Securities held-to-maturity, ACL	220		45
Municipal Bonds [Member]
Amortized cost, available for sale securities	82,211		82,774
Gross unrealized gains, available for sale securities	0		0
Gross unrealized losses, available for sale securities	(13,689)		(12,430)
Total securities available-for-sale, fair value	68,522		70,344
Available-for-Sale, Allowance for Credit Loss	0		0
Amortized cost, held to maturity securities	2,257
Gross unrealized gains, held to maturity securities	0
Gross unrealized losses, held to maturity securities	(5)
Securities held-to-maturity, at fair value	2,252
Securities held-to-maturity, ACL	0
Collateralized Mortgage-Backed Securities [Member]
Amortized cost, available for sale securities	199,747		178,740
Gross unrealized gains, available for sale securities	1,033		415
Gross unrealized losses, available for sale securities	(10,264)		(11,969)
Total securities available-for-sale, fair value	190,516		167,186
Available-for-Sale, Allowance for Credit Loss	0		0
Asset-Backed Securities [Member]
Amortized cost, available for sale securities	11,617		12,511
Gross unrealized gains, available for sale securities	2		3
Gross unrealized losses, available for sale securities	(1,019)		(1,133)
Total securities available-for-sale, fair value	10,600		11,381
Available-for-Sale, Allowance for Credit Loss	$ 0		$ 0

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