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Note 4 - Loans and Allowance for Credit Losses - Schedule of Modified Financing Receivables (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction | $ 0 | $ 0 |  | $ 0
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage |  |  | 2.20% |
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member] | Contractual Interest Rate Reduction [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction |  |  | $ 0 |
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member] | Principal Forgiveness [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction |  |  | 0 |
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member] | Extended Maturity [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction |  |  | 0 |
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member] | Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction |  |  | 1,463 |
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member] | Extended Maturity and Principal Forgiveness [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction |  |  | 0 |
Agricultural Real Estate Portfolio Segment [Member] | Land [Member] | Commercial Borrower [Member] | Extended Maturity and Interest Rate Reduction [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified, Interest Rate Reduction |  |  | $ 0 |

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- Definition Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-42 + Details
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- Definition Percentage, excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-42 + Details
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