Loans And The Allowance For Credit Losses (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable no allowance	$ 195	$ 195	$ 280
Loans, net of unearned income	96,789	96,789	98,379
Defaulted during period as modification to troubled borrower, twelve months prior to modification	49	183
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	54,779	54,779	56,033
Commercial Portfolio Segment [Member] \| Extended Maturity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Excluding Accrued Interest, Modified, Accumulated	65	65	106
Total Investor Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	8,812	8,812	8,850
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	33,198	33,198	33,496
Collateral Dependent Member \| Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	218	218	220
Collateral Dependent Member \| Total Investor Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	199	199	92
Collateral Dependent Member \| Consumer Portfolio Segment [Member] \| residential real estate and home equity loan and lines
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	$ 113	$ 113	$ 93

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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