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Loans and ACL (Summary of specific reserves by segments) (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Mar. 31, 2025 | Dec. 31, 2024 | Sep. 30, 2024 | Jun. 30, 2024
--- | --- | --- | --- | --- | ---
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Individually evaluated for impairment, ACL | $ 0 | $ 0 | $ 0 | $ 0 | $ 137
Collateral Pledged |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Individually evaluated for impairment, Loans | 1,087 |  | 254 |  |
Individually evaluated for impairment, ACL |  |  | 0 |  |
Commercial [Member] | Collateral Pledged |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Individually evaluated for impairment, Loans | 0 |  | 0 |  |
Individually evaluated for impairment, ACL | 0 |  | 0 |  |
Commercial Real Estate | Collateral Pledged |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Individually evaluated for impairment, Loans | 533 |  | 0 |  |
Individually evaluated for impairment, ACL | 0 |  | 0 |  |
Agricultural [Member] | Collateral Pledged |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Individually evaluated for impairment, Loans | 0 |  | 0 |  |
Individually evaluated for impairment, ACL | 0 |  | 0 |  |
Residential Mortgage | Collateral Pledged |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Individually evaluated for impairment, Loans | 554 |  | 254 |  |
Individually evaluated for impairment, ACL | 0 |  | 0 |  |
Consumer Portfolio Segment [Member] | Collateral Pledged |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Individually evaluated for impairment, Loans | 0 |  | 0 |  |
Individually evaluated for impairment, ACL | $ 0 |  | $ 0 |  |

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