Note 2 - Securities - Amortized Cost, Gross Unrealized Gains and Losses, and Estimated Fair Value of Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Available-for-Sale, Amortized Cost	$ 336,206	$ 376,265
Securities available for sale, gross unrealized gains	434	238
Securities available for sale, gross unrealized losses	(33,125)	(36,159)
Investment securities available for sale, at fair value (amortized cost of $336,206 and $376,265 at June 30, 2025 and December 31, 2024, respectively)	303,515	340,344
Securities available for sale, allowance for credit losses	0	0
US States and Political Subdivisions Debt Securities [Member]
Available-for-Sale, Amortized Cost	92,800	93,212
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	(15,476)	(15,336)
Investment securities available for sale, at fair value (amortized cost of $336,206 and $376,265 at June 30, 2025 and December 31, 2024, respectively)	77,324	77,876
Securities available for sale, allowance for credit losses	0	0
US Government Agencies Debt Securities [Member]
Available-for-Sale, Amortized Cost	12,408	12,944
Securities available for sale, gross unrealized gains	0	16
Securities available for sale, gross unrealized losses	(110)	(84)
Investment securities available for sale, at fair value (amortized cost of $336,206 and $376,265 at June 30, 2025 and December 31, 2024, respectively)	12,298	12,876
Securities available for sale, allowance for credit losses	0	0
Corporate Issued Asset-backed Securities [Member]
Available-for-Sale, Amortized Cost	13,070	16,065
Securities available for sale, gross unrealized gains	40	62
Securities available for sale, gross unrealized losses	(5)	(5)
Investment securities available for sale, at fair value (amortized cost of $336,206 and $376,265 at June 30, 2025 and December 31, 2024, respectively)	13,105	16,122
Securities available for sale, allowance for credit losses	0	0
Corporate Debt Securities [Member]
Available-for-Sale, Amortized Cost	58,309	58,106
Securities available for sale, gross unrealized gains	125	55
Securities available for sale, gross unrealized losses	(2,674)	(3,670)
Investment securities available for sale, at fair value (amortized cost of $336,206 and $376,265 at June 30, 2025 and December 31, 2024, respectively)	55,760	54,491
Securities available for sale, allowance for credit losses	0	0
US Small Business Administration Securities [Member]
Available-for-Sale, Amortized Cost	7,480	8,664
Securities available for sale, gross unrealized gains	34	18
Securities available for sale, gross unrealized losses	(10)	(16)
Investment securities available for sale, at fair value (amortized cost of $336,206 and $376,265 at June 30, 2025 and December 31, 2024, respectively)	7,504	8,666
Securities available for sale, allowance for credit losses	0	0
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Available-for-Sale, Amortized Cost	107,161	111,372
Securities available for sale, gross unrealized gains	228	83
Securities available for sale, gross unrealized losses	(11,375)	(12,758)
Investment securities available for sale, at fair value (amortized cost of $336,206 and $376,265 at June 30, 2025 and December 31, 2024, respectively)	96,014	98,697
Securities available for sale, allowance for credit losses	0	0
Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Available-for-Sale, Amortized Cost	44,978	75,902
Securities available for sale, gross unrealized gains	7	4
Securities available for sale, gross unrealized losses	(3,475)	(4,290)
Investment securities available for sale, at fair value (amortized cost of $336,206 and $376,265 at June 30, 2025 and December 31, 2024, respectively)	41,510	71,616
Securities available for sale, allowance for credit losses	$ 0	$ 0

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
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-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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