Investment Securities - Narrative (Details) |
3 Months Ended | 9 Months Ended | |||||
|---|---|---|---|---|---|---|---|
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Sep. 30, 2025
USD ($)
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Sep. 30, 2024
USD ($)
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Sep. 30, 2025
USD ($)
security
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Sep. 30, 2024
USD ($)
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Dec. 31, 2024
USD ($)
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Jun. 30, 2024
USD ($)
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Dec. 31, 2023
USD ($)
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| Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] | |||||||
| Proceeds from sales of available-for-sale securities | $ 2,390,000,000 | $ 9,911,000,000 | $ 8,405,000,000 | ||||
| Pre-tax gain | $ 1,000,000 | $ 1,000,000 | |||||
| Percentage of investment portfolio considered investment grade | 99.00% | 99.00% | |||||
| Allowance for credit losses on HTM investment securities | $ 0 | $ 1,000,000 | $ 0 | 1,000,000 | $ 0 | $ 1,000,000 | $ 1,000,000 |
| Provision | 0 | $ 0 | $ 0 | ||||
| Charge-offs | 0 | ||||||
| Unrealized loss | $ 4,440,000,000 | ||||||
| Number of securities in loss position | security | 1,347 | ||||||
| Asset pledged as collateral | |||||||
| Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] | |||||||
| Debt securities | $ 81,140,000,000 | $ 81,140,000,000 | $ 86,700,000,000 | ||||
| X | ||||||||||
- Definition Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity or available-for-sale where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity and available-for-sale investments determined to be temporarily impaired. No definition available.
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| X | ||||||||||
- Definition Percentage of Portfolio Considered Investment Grade No definition available.
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| X | ||||||||||
- Definition Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading). Reference 1: http://www.xbrl.org/2003/role/exampleRef
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| X | ||||||||||
- Definition Amount, excluding accrued interest, of decrease in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from writeoff. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount of unrealized and realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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| X | ||||||||||
- Definition Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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| X | ||||||||||
- Definition Amount, excluding accrued interest, of credit loss expense (reversal of expense) on investment in debt security measured at amortized cost (held-to-maturity). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount of unrealized gain (loss) on investment in marketable security. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- 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. No definition available.
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| X | ||||||||||
- Definition Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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