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Loans and Allowance for Credit Losses - Loans by Type as Percentage of Portfolio (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024 | Jun. 30, 2025 | Sep. 30, 2024 | Jun. 30, 2024 | Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans | $ 2,909,928 | $ 1,545,640 |  |  |  |
Allowance for credit loss | $ 34,754 | $ 16,552 | $ 34,798 | $ 16,490 | $ 16,152 | $ 15,685
Percentage of allowance for credit losses | 1.19% | 1.07% |  |  |  |
Loans, net | $ 2,875,174 | $ 1,529,088 |  |  |  |
Agricultural [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans | $ 51,183 | $ 48,221 |  |  |  |
Percentage of loans | 1.80% | 3.10% |  |  |  |
Percentage of increase decrease of loans | 6.10% |  |  |  |  |
Allowance for credit loss | $ 233 | $ 90 | 219 | 110 | 112 | 94
Commercial and Industrial [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans | $ 352,876 | $ 228,256 |  |  |  |
Percentage of loans | 12.10% | 14.80% |  |  |  |
Percentage of increase decrease of loans | 54.60% |  |  |  |  |
Allowance for credit loss | $ 6,297 | $ 2,260 | 5,240 | 2,470 | 2,161 | 2,216
Commercial Real Estate Portfolio Segment [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans | $ 1,728,774 | $ 901,130 |  |  |  |
Percentage of loans | 59.40% | 58.30% |  |  |  |
Percentage of increase decrease of loans | 91.80% |  |  |  |  |
Allowance for credit loss | $ 17,575 | $ 9,460 | 18,311 | 9,220 | 9,360 | 8,820
Consumer Portfolio Segment [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans | $ 27,328 | $ 29,412 |  |  |  |
Percentage of loans | 0.90% | 1.90% |  |  |  |
Percentage of increase decrease of loans | (7.10%) |  |  |  |  |
Allowance for credit loss | $ 736 | $ 733 | 772 | 761 | 795 | 823
Construction Real Estate [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans | $ 18,441 | $ 17,042 |  |  |  |
Percentage of loans | 0.60% | 1.10% |  |  |  |
Percentage of increase decrease of loans | 8.20% |  |  |  |  |
Allowance for credit loss | $ 83 | $ 59 | 90 | 36 | 49 | 58
Residential Portfolio Segment [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans | $ 728,843 | $ 281,701 |  |  |  |
Percentage of loans | 25.00% | 18.20% |  |  |  |
Percentage of increase decrease of loans | 158.70% |  |  |  |  |
Allowance for credit loss | $ 9,826 | $ 3,890 | 10,161 | 3,833 | 3,625 | 3,644
Loans to other financial institutions [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans | $ 2,483 | $ 39,878 |  |  |  |
Percentage of loans | 0.10% | 2.60% |  |  |  |
Percentage of increase decrease of loans | (93.80%) |  |  |  |  |
Allowance for credit loss | $ 4 | $ 60 | $ 5 | $ 60 | $ 50 | $ 30

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