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Amount, before allowance for credit loss, of accrued interest on financing receivable.

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Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Loans and Leases - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest	$ 249	$ 249		$ 257
Net loans and leases	64,621	64,621		63,418
Loans and leases	$ 65,330	$ 65,330		64,156
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		$ 8	$ 1
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
Commercial \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan grades	1	1
Commercial \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan grades	16	16
Commercial \| Loans to mortgage companies
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 4,759	$ 4,759		4,703
Commercial \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	37,296	37,296		35,905
Commercial \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	13,595	13,595		13,563
Finance and Insurance Companies \| Commercial \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 4,300	$ 4,300
Financial Services Industry Loans \| Commercial \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage contributed	24.00%	24.00%
C&I \| Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 311	$ 311		400
C&I \| Commercial \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	32,537	32,537		31,202
C&I \| Commercial \| Commercial and industrial \| Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	126	126
Commercial Real Estate \| Commercial \| Commercial real estate \| Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	185	185
Asset Pledged as Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net loans and leases	45,700	45,700		45,100
Asset Pledged as Collateral \| C&I
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit loss, writeoff, collateral	27	46
Asset Pledged as Collateral \| Home Equity Line of Credit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	5	5		5
Financing receivable, allowance for credit loss, writeoff, collateral		1	$ 0
Asset Pledged as Collateral \| Real estate installment loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 43	$ 43		$ 46