Note 2 - Securities - Amortized Cost, Gross Unrealized Gains and Losses, and Estimated Fair Value of Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Available-for-Sale, Amortized Cost	$ 295,849	$ 376,265
Securities available for sale, gross unrealized gains	682	238
Securities available for sale, gross unrealized losses	(26,221)	(36,159)
Investment securities available for sale, at fair value (amortized cost of $295,849 and $376,265, respectively)	270,310	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	92,148	93,212
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	(11,896)	(15,336)
Investment securities available for sale, at fair value (amortized cost of $295,849 and $376,265, respectively)	80,252	77,876
Securities available for sale, allowance for credit losses	0	0
US Government Agencies Debt Securities [Member]
Available-for-Sale, Amortized Cost	11,927	12,944
Securities available for sale, gross unrealized gains	28	16
Securities available for sale, gross unrealized losses	(12)	(84)
Investment securities available for sale, at fair value (amortized cost of $295,849 and $376,265, respectively)	11,943	12,876
Securities available for sale, allowance for credit losses	0	0
Corporate Issued Asset-backed Securities [Member]
Available-for-Sale, Amortized Cost	7,963	16,065
Securities available for sale, gross unrealized gains	2	62
Securities available for sale, gross unrealized losses	(4)	(5)
Investment securities available for sale, at fair value (amortized cost of $295,849 and $376,265, respectively)	7,961	16,122
Securities available for sale, allowance for credit losses	0	0
Corporate Debt Securities [Member]
Available-for-Sale, Amortized Cost	39,772	58,106
Securities available for sale, gross unrealized gains	251	55
Securities available for sale, gross unrealized losses	(1,222)	(3,670)
Investment securities available for sale, at fair value (amortized cost of $295,849 and $376,265, respectively)	38,801	54,491
Securities available for sale, allowance for credit losses	0	0
US Small Business Administration Securities [Member]
Available-for-Sale, Amortized Cost	6,293	8,664
Securities available for sale, gross unrealized gains	18	18
Securities available for sale, gross unrealized losses	(18)	(16)
Investment securities available for sale, at fair value (amortized cost of $295,849 and $376,265, respectively)	6,293	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	101,618	111,372
Securities available for sale, gross unrealized gains	379	83
Securities available for sale, gross unrealized losses	(10,341)	(12,758)
Investment securities available for sale, at fair value (amortized cost of $295,849 and $376,265, respectively)	91,656	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	36,128	75,902
Securities available for sale, gross unrealized gains	4	4
Securities available for sale, gross unrealized losses	(2,728)	(4,290)
Investment securities available for sale, at fair value (amortized cost of $295,849 and $376,265, respectively)	33,404	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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Amount excluding accrued interest, of allowance for credit loss 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 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
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-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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