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Loans And The Allowance For Credit Losses (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable no allowance	$ 100		$ 109
Loans, net of unearned income	97,926		95,637
Defaulted during period as modification to troubled borrower, twelve months prior to modification	38	$ 24
Unfunded Loan Commitment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Excluding Accrued Interest, Modified, Accumulated		$ 124
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	56,089		53,898
Investor Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	9,644		9,106
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	32,193		32,633
Collateral Dependent Member \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	313		337
Collateral Dependent Member \| Investor Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	98		121
Collateral Dependent Member \| Consumer \| residential real estate and home equity loan and lines
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	$ 143		$ 127