Fair Value Option - Summary of Fair Value and Unpaid Principal Balance (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Fair Value, Option, Quantitative Disclosures [Line Items]
Client share repurchase asset, Fair Value	$ 100	$ 0
Client share repurchase liability, Fair Value	100	0
Commercial loans held for sale
Fair Value, Option, Quantitative Disclosures [Line Items]
Commercial loans held for sale, Fair Value	795	626
Commercial loans held for sale, Unpaid Principal Balance	890	721
Fair Value Over (Under) Unpaid Principal Balance	(95)	(95)
Client share repurchase asset
Fair Value, Option, Quantitative Disclosures [Line Items]
Client share repurchase asset, Fair Value	137	20
Client share repurchase asset, Unpaid Principal Balance	137	20
Fair Value Over (Under) Unpaid Principal Balance	0	0
Fixed rate long-term debt
Fair Value, Option, Quantitative Disclosures [Line Items]
Fixed rate long-term debt, Fair Value	802	831
Fixed rate long-term debt, Unpaid Principal Balance	775	791
Fair Value Over (Under) Unpaid Principal Balance	27	40
Fixed rate long-term debt \| Structured notes
Fair Value, Option, Quantitative Disclosures [Line Items]
Hybrid instruments, structured notes, Fair Value	7,890	7,435
Hybrid instruments, Unpaid Principal Balance	7,499	7,093
Fair Value Over (Under) Unpaid Principal Balance	391	342
Structured deposits
Fair Value, Option, Quantitative Disclosures [Line Items]
Hybrid instruments, structured deposits, Fair Value	3,752	3,570
Hybrid instruments, Unpaid Principal Balance	3,372	3,260
Fair Value Over (Under) Unpaid Principal Balance	380	310
Client share repurchase liability
Fair Value, Option, Quantitative Disclosures [Line Items]
Client share repurchase liability, Fair Value	137	20
Client share repurchase liability, Unpaid Principal Balance	137	20
Fair Value Over (Under) Unpaid Principal Balance	$ 0	$ 0

Fair Value Over (Under) Unpaid Principal Balance

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Fixed-rate debt accounted for under fair value option.

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Unpaid Principal Balance Commercial Syndicated Loans Held For Sale Carried At Fair Value

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Unpaid principal balance on fixed-rate debt accounted for under FVO.

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Unpaid Principal Balance On Hybrid Instruments At Fair Value Option

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- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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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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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Fair value portion of other assets.

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Fair value portion of other liabilities.

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