Note 9 - Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Non-recurring Basis (Details) - Fair Value, Nonrecurring [Member] - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2026	Dec. 31, 2025
Collateral dependent loans, fair value	$ 3,681	$ 1,988
Collateral depended loans, total loss	1,319	931
Other Real Estate Owned and Receivables, Fair Value		226
Total, total loss		0
Fair Value, Inputs, Level 1 [Member]
Collateral dependent loans, fair value	0	0
Other Real Estate Owned and Receivables, Fair Value		0
Fair Value, Inputs, Level 2 [Member]
Collateral dependent loans, fair value	0	0
Other Real Estate Owned and Receivables, Fair Value		0
Fair Value, Inputs, Level 3 [Member]
Collateral dependent loans, fair value	3,681	1,988
Other Real Estate Owned and Receivables, Fair Value		226
Commercial Loans [Member]
Collateral dependent loans, fair value	0	84
Collateral depended loans, total loss	221	0
Commercial Loans [Member] \| Fair Value, Inputs, Level 1 [Member]
Collateral dependent loans, fair value	0	0
Commercial Loans [Member] \| Fair Value, Inputs, Level 2 [Member]
Collateral dependent loans, fair value	0	0
Commercial Loans [Member] \| Fair Value, Inputs, Level 3 [Member]
Collateral dependent loans, fair value	0	84
Agricultural Loans [Member]
Collateral dependent loans, fair value	1,722	1,904
Collateral depended loans, total loss	989	931
Agricultural Loans [Member] \| Fair Value, Inputs, Level 1 [Member]
Collateral dependent loans, fair value	0	0
Agricultural Loans [Member] \| Fair Value, Inputs, Level 2 [Member]
Collateral dependent loans, fair value	0	0
Agricultural Loans [Member] \| Fair Value, Inputs, Level 3 [Member]
Collateral dependent loans, fair value	1,722	1,904
Real Estate Loan [Member]
Collateral depended loans, total loss		0
Real Estate Loan [Member] \| Commercial Portfolio Segment [Member]
Collateral dependent loans, fair value	1,959
Collateral depended loans, total loss	109
Real Estate Loan [Member] \| Residential Portfolio Segment [Member]
RE – Residential, fair value		91
Real Estate Loan [Member] \| Fair Value, Inputs, Level 1 [Member]
RE – Residential, fair value		0
Real Estate Loan [Member] \| Fair Value, Inputs, Level 1 [Member] \| Commercial Portfolio Segment [Member]
Collateral dependent loans, fair value	0
Real Estate Loan [Member] \| Fair Value, Inputs, Level 2 [Member]
RE – Residential, fair value		0
Real Estate Loan [Member] \| Fair Value, Inputs, Level 2 [Member] \| Commercial Portfolio Segment [Member]
Collateral dependent loans, fair value	0
Real Estate Loan [Member] \| Fair Value, Inputs, Level 3 [Member]
RE – Residential, fair value		91
Real Estate Loan [Member] \| Fair Value, Inputs, Level 3 [Member] \| Commercial Portfolio Segment [Member]
Collateral dependent loans, fair value	1,959
Equity Lines of Credit [Member] \| Residential Portfolio Segment [Member]
Equity lines of credit, fair value	135	135
Equity lines of credit, total loss	0	0
Equity Lines of Credit [Member] \| Fair Value, Inputs, Level 1 [Member] \| Residential Portfolio Segment [Member]
Equity lines of credit, fair value	0
Equity Lines of Credit [Member] \| Fair Value, Inputs, Level 2 [Member] \| Residential Portfolio Segment [Member]
Equity lines of credit, fair value	0
Equity Lines of Credit [Member] \| Fair Value, Inputs, Level 3 [Member] \| Residential Portfolio Segment [Member]
Equity lines of credit, fair value	$ 135	$ 135

Amount of fair value loss or gain for collateral dependent loans.

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+ References

No definition available.

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- Definition

Fair value portion of other real estate.

+ References

No definition available.

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+ References

No definition available.

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Amount of fair value loss or gain for other real estate owned and receivables.

+ References

No definition available.

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Amount of fair value loss or gain for other real estate owned.

+ References

No definition available.

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Amount of fair value loss or gain for receivables.

+ References

No definition available.

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- Definition

Fair value portion of receivables, including, but not limited to, trade account receivables, note receivables, and loan receivables.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-11

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-11

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-10

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2E

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