Note 2 - Securities - Amortized Cost and Estimated Fair Value of Investment Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Available-for-Sale, Amortized Cost	$ 336,206	$ 376,265
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
Collateralized Mortgage-Backed Securities [Member]
Due within one year, amortized cost	5,929	26,690
Due within one year, estimated fair value	5,851	26,509
Due after one through five years, amortized cost	10,404	11,564
Due after one through five years, estimated fair value	10,373	11,539
Due after five through ten years, amortized cost	7,962	8,080
Due after five through ten years, estimated fair value	7,633	7,609
Due after ten years, amortized cost	127,844	140,940
Due after ten years, estimated fair value	113,667	124,656
Available-for-Sale, Amortized Cost	152,139	187,274
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)	137,524	170,313
Investment Securities, Excluding Mortgage Backed Securities [Member]
Due within one year, amortized cost	0	0
Due within one year, estimated fair value	0	0
Due after one through five years, amortized cost	26,013	21,559
Due after one through five years, estimated fair value	25,046	20,751
Due after five through ten years, amortized cost	54,904	58,535
Due after five through ten years, estimated fair value	51,350	53,321
Due after ten years, amortized cost	103,150	108,897
Due after ten years, estimated fair value	89,595	95,959
Available-for-Sale, Amortized Cost	184,067	188,991
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)	$ 165,991	$ 170,031

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

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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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Amount excluding accrued interest, of 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/2009/role/commonPracticeRef
-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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