Goodwill and Other Intangible Assets - Schedule of Other Intangible Assets (Details) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Goodwill [Line Items] | ||
| Gross Carrying Amount | $ 1,240 | $ 131 |
| Accumulated Amortization | (241) | (101) |
| Net Carrying Value | 999 | 30 |
| CDI | ||
| Goodwill [Line Items] | ||
| Gross Carrying Amount | 937 | 89 |
| Accumulated Amortization | (208) | (84) |
| Net Carrying Value | 729 | 5 |
| Wealth Customer Relationships | ||
| Goodwill [Line Items] | ||
| Gross Carrying Amount | 262 | |
| Accumulated Amortization | (14) | |
| Net Carrying Value | 248 | |
| Client Relationships | ||
| Goodwill [Line Items] | ||
| Gross Carrying Amount | 26 | 26 |
| Accumulated Amortization | (19) | (17) |
| Net Carrying Value | 7 | 9 |
| Other | ||
| Goodwill [Line Items] | ||
| Gross Carrying Amount | 15 | 16 |
| Accumulated Amortization | 0 | 0 |
| Net Carrying Value | $ 15 | $ 16 |
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- Definition Amount of accumulated amortization of finite-lived intangible asset. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before accumulated amortization, of finite-lived intangible asset. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, after accumulated amortization, of finite-lived intangible asset. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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