Loans and Allowances for Credit Losses, Modifications (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified in Period, Amount	$ 100.0	$ 130.0
Financing Receivable, Modified, Subsequent Default	$ 31.0
Number of Days Past Due Following Modification to be Considered a Payment Default	30 days
Commercial [Member] | Extended Maturity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified, Subsequent Default	$ 25.0
Commercial Portfolio Segment and Loans to individuals Portfolio Segment | Extended Maturity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified in Period, Amount	91.0
Healthcare [Member] | Commercial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified in Period, Amount	72.0	47.0
Healthcare and General business member | Commercial [Member] | Extended Maturity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified in Period, Amount		93.0
Healthcare and Loans to individuals member | Commercial Portfolio Segment and Loans to individuals Portfolio Segment | Extended Maturity and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified in Period, Amount		36.0
Energy [Member] | Commercial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified in Period, Amount	9.3
General business member | Commercial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified in Period, Amount		67.0
US Government Agency Insured Loans | Residential mortgage [Member] | Loans to individuals [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified in Period, Amount	8.6	13.0
Financing Receivable, Modified, Subsequent Default		$ 4.8
US Government Agency Insured Loans | Residential mortgage [Member] | Loans to individuals [Member] | Extended Maturity and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified in Period, Amount	8.6
Financing Receivable, Modified, Subsequent Default	$ 5.2