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Note 4 - Loans and Allowance for Credit Losses - Schedule of Modified Financing Receivables (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2026 | Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025
Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage | 0.13% | 0.23% | 0.37% | 0.25%
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification | 0.00% | 0.00% | 0.00% | 0.00%
Financing Receivable, Modified, Weighted Average Term Increase from Modification (Month) | 10 months | 4 months | 8 months | 6 months
Extended Maturity [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 1,415 | $ 2,491 | $ 3,161 | $ 2,577
Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 73 |  | $ 961 | $ 73
Extended Maturity and Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount |  | $ 0 |  |
Commercial Portfolio Segment [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage | 0.69% | 0.82% | 0.91% | 0.93%
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification | 0.00% | 0.00% | 0.00% | 0.00%
Financing Receivable, Modified, Weighted Average Term Increase from Modification (Month) | 10 months | 5 months | 9 months | 10 months
Commercial Portfolio Segment [Member] | Extended Maturity [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 1,415 | $ 1,157 | $ 1,870 | $ 1,243
Commercial Portfolio Segment [Member] | Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 73 |  | $ 73 | $ 73
Commercial Portfolio Segment [Member] | Extended Maturity and Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount |  | $ 0 |  |
Commercial Real Estate Portfolio Segment [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage | 0.00% | 0.19% | 0.13% | 0.19%
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification | 0.00% | 0.00% | 0.00% | 0.00%
Financing Receivable, Modified, Weighted Average Term Increase from Modification (Month) | 0 months | 3 months | 0 months | 3 months
Commercial Real Estate Portfolio Segment [Member] | Extended Maturity [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 0 | $ 1,334 | $ 0 | $ 1,334
Commercial Real Estate Portfolio Segment [Member] | Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 0 |  | $ 888 | $ 0
Commercial Real Estate Portfolio Segment [Member] | Extended Maturity and Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount |  | $ 0 |  |
Agricultural Portfolio Segment [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage | 0.00% | 0.00% | 1.49% | 0.00%
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification | 0.00% | 0.00% | 0.00% | 0.00%
Financing Receivable, Modified, Weighted Average Term Increase from Modification (Month) | 0 months | 0 months | 6 months | 0 months
Agricultural Portfolio Segment [Member] | Extended Maturity [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 0 | $ 0 | $ 1,291 | $ 0
Agricultural Portfolio Segment [Member] | Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 0 |  | $ 0 | $ 0
Agricultural Portfolio Segment [Member] | Extended Maturity and Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount |  | $ 0 |  |
Residential Mortgage [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage | 0.00% | 0.00% | 0.00% | 0.00%
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification | 0.00% | 0.00% | 0.00% | 0.00%
Financing Receivable, Modified, Weighted Average Term Increase from Modification (Month) | 0 months | 0 months | 0 months | 0 months
Residential Mortgage [Member] | Extended Maturity [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 0 | $ 0 | $ 0 | $ 0
Residential Mortgage [Member] | Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 0 |  | $ 0 | $ 0
Residential Mortgage [Member] | Extended Maturity and Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount |  | $ 0 |  |
Residential Portfolio Segment [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage | 0.00% | 0.00% | 0.00% | 0.00%
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification | 0.00% | 0.00% | 0.00% | 0.00%
Financing Receivable, Modified, Weighted Average Term Increase from Modification (Month) | 0 months | 0 months | 0 months | 0 months
Residential Portfolio Segment [Member] | Extended Maturity [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 0 | $ 0 | $ 0 | $ 0
Residential Portfolio Segment [Member] | Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 0 |  | $ 0 | $ 0
Residential Portfolio Segment [Member] | Extended Maturity and Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount |  | $ 0 |  |
Consumer Portfolio Segment [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage | 0.00% | 0.00% | 0.00% | 0.00%
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification | 0.00% | 0.00% | 0.00% | 0.00%
Financing Receivable, Modified, Weighted Average Term Increase from Modification (Month) | 0 months | 0 months | 0 months | 0 months
Consumer Portfolio Segment [Member] | Extended Maturity [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 0 | $ 0 | $ 0 | $ 0
Consumer Portfolio Segment [Member] | Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 0 |  | $ 0 | $ 0
Consumer Portfolio Segment [Member] | Extended Maturity and Payment Deferral [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount |  | $ 0 |  |

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