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Loans and Allowances for Credit Losses, Modifications (Details) - USD ($) $ in Millions | 9 Months Ended
--- | ---
Sep. 30, 2025 | Sep. 30, 2024
Financing Receivable, Loan Modifications [Line Items] |  |
Financing Receivable, Modified in Period, Amount | $ 76.0 | $ 147.0
Financing Receivable, Modified, Subsequent Default | $ 14.0 | 32.0
Number of Days Past Due Following Modification to be Considered a Payment Default | 30 days |
Commercial [Member] | Extended Maturity |  |
Financing Receivable, Loan Modifications [Line Items] |  |
Financing Receivable, Modified in Period, Amount | $ 48.0 | 141.0
Financing Receivable, Modified, Subsequent Default |  | 28.0
Commercial real estate [Member] |  |
Financing Receivable, Loan Modifications [Line Items] |  |
Financing Receivable, Modified in Period, Amount | 18.0 |
Healthcare [Member] | Commercial [Member] |  |
Financing Receivable, Loan Modifications [Line Items] |  |
Financing Receivable, Modified in Period, Amount | 32.0 | 90.0
Healthcare [Member] | Commercial [Member] | Extended Maturity |  |
Financing Receivable, Loan Modifications [Line Items] |  |
Financing Receivable, Modified, Subsequent Default | 5.2 |
Energy [Member] | Commercial [Member] |  |
Financing Receivable, Loan Modifications [Line Items] |  |
Financing Receivable, Modified in Period, Amount |  | 43.0
General business [Member] | Commercial [Member] |  |
Financing Receivable, Loan Modifications [Line Items] |  |
Financing Receivable, Modified in Period, Amount | 15.0 |
US Government Agency Insured Loans [Member] | Residential Mortgage [Member] | Loans to individuals [Member] |  |
Financing Receivable, Loan Modifications [Line Items] |  |
Financing Receivable, Modified in Period, Amount | 11.0 |
US Government Agency Insured Loans [Member] | Residential Mortgage [Member] | Loans to individuals [Member] | Extended Maturity and Interest Rate Reduction |  |
Financing Receivable, Loan Modifications [Line Items] |  |
Financing Receivable, Modified in Period, Amount | 11.0 | 5.9
Financing Receivable, Modified, Subsequent Default | $ 7.1 | $ 4.3

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