Goodwill and Other Intangible Assets - Schedule of Intangible Assets and Accumulated Amortization Included in the Consolidated Statements of Condition (Details) - USD ($) $ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
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| Intangible Assets [Line Items] | ||
| Gross Carrying Amount | $ 397 | $ 397 |
| Accumulated Amortization | (300) | (292) |
| Net Carrying Value | 97 | 105 |
| Core deposit intangibles | ||
| Intangible Assets [Line Items] | ||
| Gross Carrying Amount | 354 | 354 |
| Accumulated Amortization | (271) | (264) |
| Net Carrying Value | 83 | 90 |
| Client relationships | ||
| Intangible Assets [Line Items] | ||
| Gross Carrying Amount | 32 | 32 |
| Accumulated Amortization | (21) | (20) |
| Net Carrying Value | 11 | 12 |
| Other | ||
| Intangible Assets [Line Items] | ||
| Gross Carrying Amount | 11 | 11 |
| Accumulated Amortization | (8) | (8) |
| Net Carrying Value | $ 3 | $ 3 |
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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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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- Definition Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before accumulated amortization of finite-lived intangible assets classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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