Note 2 - Securities 1 (Details Textual) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2026 USD ($)	Dec. 31, 2025
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss	$ 1.1
Debt Securities, Held-to-Maturity, Accrued Interest, after Allowance for Credit Loss	$ 376.0
Weighted Average Re-pricing Term (Year)	4 years 3 months 18 days	4 years 7 months 6 days
US Treasury Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	14
Available-for-Sale Securities, Number of Securities	14
US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	114
Available-for-Sale Securities, Number of Securities	128
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	81
Available-for-Sale Securities, Number of Securities	95
Corporate Debt Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	3
Available-for-Sale Securities, Number of Securities	4

The number of investment positions in available-for-sale investments.

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- Definition

The weighted average period of time between re-pricing of the portfolio.

+ References

No definition available.

+ Details

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- Definition

Amount, after allowance for credit loss, of accrued interest 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 2A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2A

Reference 2: 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

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-3A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-3B

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- Definition

Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-4

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- Definition

Amount, after allowance for credit loss, of accrued interest on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5C

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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-Section 50
-Paragraph 3A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3A

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