Loans And The Allowance For Credit Losses (Financial Impact Of Modifications To Troubled Borrowers) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Modifications [Line Items]
Defaulted during period as modification to troubled borrower, twelve months prior to modification	$ 257	$ 116
Commercial And Industrial [Member] \| Extended Maturity
Financing Receivable, Modifications [Line Items]
Financial Effect, Term Extension	1 year 11 months 1 day	1 year
Commercial And Industrial [Member] \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Financial Effect, Payments deferral		0.5
Commercial And Industrial [Member] \| Extended Maturity and Interest Rate Reduction
Financing Receivable, Modifications [Line Items]
Financial Effect, Term Extension	2 years 29 days
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification	1.00%
Commercial And Industrial [Member] \| Extended Maturity and Payment Deferral
Financing Receivable, Modifications [Line Items]
Financial Effect, Term Extension		3 years
Financial Effect, Payments deferral		3
Commercial Real Estate Mortgage - Owner-Occupied [Member] \| Extended Maturity
Financing Receivable, Modifications [Line Items]
Financial Effect, Term Extension	3 years 6 months 29 days	1 year 6 months
Commercial Real Estate Construction - Owner-Occupied [Member] \| Extended Maturity
Financing Receivable, Modifications [Line Items]
Financial Effect, Term Extension		3 months
Commercial investor real estate mortgage [Member] \| Extended Maturity
Financing Receivable, Modifications [Line Items]
Financial Effect, Term Extension	9 months 29 days	9 months 29 days
Commercial investor real estate mortgage [Member] \| Contractual Interest Rate Reduction
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification	1.00%
Residential First Mortgage [Member] \| Extended Maturity
Financing Receivable, Modifications [Line Items]
Financial Effect, Term Extension	7 years	6 years
Residential First Mortgage [Member] \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Financial Effect, Payments deferral	0.67	0.83
Residential First Mortgage [Member] \| Extended Maturity and Interest Rate Reduction
Financing Receivable, Modifications [Line Items]
Financial Effect, Term Extension	5 years	7 years
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification	1.00%	1.00%
Home Equity Lines of Credit[Member] \| Extended Maturity
Financing Receivable, Modifications [Line Items]
Financial Effect, Term Extension		18 years
Home Equity Lines of Credit[Member] \| Extended Maturity and Interest Rate Reduction
Financing Receivable, Modifications [Line Items]
Financial Effect, Term Extension	23 years	21 years
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification	2.00%	1.00%
Home Equity Loan [Member] \| Extended Maturity
Financing Receivable, Modifications [Line Items]
Financial Effect, Term Extension	14 years	14 years
Home Equity Loan [Member] \| Extended Maturity and Interest Rate Reduction
Financing Receivable, Modifications [Line Items]
Financial Effect, Term Extension	24 years	17 years
Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification	3.00%	2.00%

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Amortized cost of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

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