Intangible Assets - Schedule of Finite-Lived Intangible Assets (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
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| Intangible Asset, Finite-Lived [Line Items] | ||
| Gross Carrying Amount | $ 721 | $ 721 |
| Accumulated Amortization | (388) | (340) |
| Net Carrying Value | 333 | 381 |
| Core deposit intangible | ||
| Intangible Asset, Finite-Lived [Line Items] | ||
| Gross Carrying Amount | 700 | 700 |
| Accumulated Amortization | (379) | (332) |
| Net Carrying Value | 321 | 368 |
| Other intangible assets | ||
| Intangible Asset, Finite-Lived [Line Items] | ||
| Gross Carrying Amount | 21 | 21 |
| Accumulated Amortization | (9) | (8) |
| Net Carrying Value | $ 12 | $ 13 |
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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 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/2009/role/commonPracticeRef
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- Definition Amount, before accumulated amortization, of finite- and indefinite-lived intangible assets and capitalized cost for software to be sold, leased, or marketed. Excludes goodwill. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after accumulated amortization, of finite- and indefinite-lived intangible assets and capitalized cost for software to be sold, leased, or marketed. Excludes goodwill. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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