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Loans and ACL - Summary of Loan Modification Effects (Details) | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024
Commercial and industrial: Secured | Other-Than-Insignificant Payment Delay |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Payment Delay Term | 8 months | 4 months
Weighted-Average Interest Rate Reduction | 10.00% |
Commercial and industrial: Secured | Term Extension |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Weighted-Average Term Extension (Years) | 1 year 10 days | 3 years
Commercial mortgage owner occupied | Other-Than-Insignificant Payment Delay |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Payment Delay Term |  | 7 months
Commercial mortgage owner occupied | Term Extension |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Weighted-Average Term Extension (Years) | 15 years | 3 years
Agricultural mortgage | Other-Than-Insignificant Payment Delay |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Payment Delay Term | 4 months | 5 months
Agricultural mortgage | Term Extension |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Weighted-Average Term Extension (Years) |  | 6 years 3 months 7 days
Agricultural other | Other-Than-Insignificant Payment Delay |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Payment Delay Term |  | 4 months
Agricultural other | Interest Rate Reduction |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Weighted-Average Interest Rate Reduction |  | 0.50%
Agricultural other | Term Extension |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Weighted-Average Term Extension (Years) | 6 months | 3 months 29 days
Senior Lien | Other-Than-Insignificant Payment Delay |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Payment Delay Term | 6 months |
Consumer: Secured - indirect | Term Extension |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Weighted-Average Term Extension (Years) |  | 1 year 3 months 29 days

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