Investment securities - Additional Information (Detail) |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
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Jun. 30, 2025
USD ($)
security
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Jun. 30, 2024
USD ($)
|
Jun. 30, 2025
USD ($)
security
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Jun. 30, 2024
USD ($)
|
Dec. 31, 2024
USD ($)
|
|
| Investments, Debt and Equity Securities [Abstract] | |||||
| Realized gain | $ 0 | $ 0 | $ 0 | $ 0 | |
| Number of debt securities with aggregate gross unrealized losses | security | 3,427 | 3,427 | |||
| Unrealized losses on individual debt securities | $ 1,100,000,000 | ||||
| Cost method equity securities | $ 730,000,000 | 730,000,000 | |||
| Allowance for credit losses | 0 | 0 | $ 0 | ||
| Investment securities pledged to secure debt carrying value | 5,800,000,000 | 5,800,000,000 | 6,200,000,000 | ||
| Carrying value of investment securities pledged related to repurchase transactions | $ 82,000,000 | $ 82,000,000 | $ 71,000,000 | ||
| X | ||||||||||
- Definition Carrying value of investment securities pledged. No definition available.
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- Definition Carrying value of investment securities pledged related to repurchase transactions.. No definition available.
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- Definition Number of debt securities with gross losses. No definition available.
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- Definition Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of 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), 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/2009/role/commonPracticeRef
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| X | ||||||||||
- Definition Amount of unrealized gain (loss) on 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/2009/role/commonPracticeRef
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| X | ||||||||||
- Definition Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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