Asset Quality - Additional Information (Details) $ in Millions	12 Months Ended
Dec. 31, 2025 USD ($) loan	Dec. 31, 2024 USD ($) loan	Dec. 31, 2023 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of carrying amount of our commercial nonperforming loans outstanding	76.00%
Percentage of nonperforming loans outstanding face value	82.00%
Percentage of loans held for sale and other nonperforming assets	83.00%
Net reduction to interest income	$ 49	$ 54	$ 37
Mortgage loans in process of foreclosure	70	72
Loan restructuring trial modifications amount	595	534	295
Commitments outstanding to lend additional funds	$ 110	$ 15
Trial Modification Plans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loan modifications \| loan	167	120
Loan restructuring trial modifications amount	$ 26	$ 20
Total commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan restructuring trial modifications amount	565	499	269
Total consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan restructuring trial modifications amount	30	35	26
Continuing Operations \| Total commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase (decrease) in ALLL	$ 41
Increase (decrease) in ALLL (as a percent)	4.00%
Continuing Operations \| Total consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase (decrease) in ALLL	$ (23)
Increase (decrease) in ALLL (as a percent)	(6.20%)
Commercial and Industrial \| Total commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan restructuring trial modifications amount	$ 304	163	263
Real estate — commercial mortgage \| Total commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan restructuring trial modifications amount	231	$ 307	$ 6
Non-performing Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonperforming loans on nonaccrual status with no allowance	$ 386

Financing Receivable, Allowance For Credit Loss, Percentage

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Financing Receivable, Modifications, Number of Loans

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Net reduction to interest income.

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Percentage of carrying amount of our commercial nonperforming loans outstanding.

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Percentage of loans held for sale and other nonperforming assets.

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Percentage of nonperforming loans outstanding face value.

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Amount of increase (decrease) in allowance for credit loss on financing receivable.

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Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

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Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable.

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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