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Loans And The Allowance For Credit Losses (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable no allowance	$ 114		$ 114		$ 109
Loans, net of unearned income	99,200		99,200		95,637
Defaulted during period as modification to troubled borrower, twelve months prior to modification	32	$ 23	70	$ 48
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	57,235		57,235		53,898
Investor Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	9,969		9,969		9,106
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	31,996		31,996		32,633
Collateral Dependent Member \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	249		249		337
Collateral Dependent Member \| Investor Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	122		122		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	$ 149		$ 149		$ 127