Loans and Leases - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest	$ 271	$ 287
Net loans and leases	61,750	60,519
Loans and leases	62,565	61,292
Financing receivable, allowance for credit loss, writeoff, collateral	$ 2	1
Credit Card Workout Program rate reduction, interest rate floor	0.00%
Credit Card Workout Program term extension, maximum period	5 years
Loans modified with subsequent default, amount	$ 19	28
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Credit Card Hardship Program, rate and payment reduction, period	6 months
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Credit Card Hardship Program, rate and payment reduction, period	1 year
Asset Pledged as Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net loans and leases	$ 45,800	46,100
Asset Pledged as Collateral \| General C I
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit loss, writeoff, collateral	75	144
Asset Pledged as Collateral \| Home Equity Line of Credit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	6	6
Asset Pledged as Collateral \| R E Installment Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 36	27
Commercial \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan grades	1
Commercial \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan grades	16
Commercial \| Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 352	250
Commercial \| Loans to mortgage companies
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	3,471	2,024
Commercial \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 33,428	32,633
Commercial \| Commercial and industrial \| Financial Services Industry Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage contributed	21.00%
Commercial \| Commercial and industrial \| Finance And Insurance Companies
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 3,700
Commercial \| Commercial and industrial \| Collateral Pledged \| General C I
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	109
Commercial \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	14,421	14,216
Commercial \| Commercial real estate \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	14,421	$ 14,216
Commercial \| Commercial real estate \| Collateral Pledged \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 243

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