Loans and Allowances for Credit Losses, Modifications (Details) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($)
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified in Period, Amount	$ 130.0
Number of Days Past Due Following Modification to be Considered a Payment Default	30 days
General business member | Commercial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified in Period, Amount	$ 67.0
Healthcare [Member] | Commercial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modified in Period, Amount	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
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	13.0
Financing Receivable, Modified, Subsequent Default	$ 4.8