Net Trading Gains (Losses) (Detail) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Investments, Debt and Equity Securities [Abstract] | ||||
| Debt Securities, Trading, Realized Gain (Loss) | $ (186) | $ 42 | $ (309) | $ 62 |
| Debt Securities, Trading, Unrealized Gain (Loss) | (1,446) | 21 | (2,271) | 576 |
| Net Trading Gains (Losses) | $ (1,632) | $ 63 | $ (2,580) | $ 638 |
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- Definition Amount of unrealized and realized gain (loss) on 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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- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of unrealized gain (loss) on 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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- References No definition available.
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