Investments (Details) - Table - AFS Securities (Redemption Terms) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| AFS Securities | ||
| Amortized Cost: Total | $ 19,704 | $ 20,144 |
| AFS securities | 19,802 | 20,253 |
| U.S. Treasury obligations: | ||
| AFS Securities | ||
| Amortized Cost: Due within Year 1 | 1,644 | 1,776 |
| Amortized Cost: Due Year 1-5 | 4,658 | 4,608 |
| Amortized Cost: Total | 6,302 | 6,384 |
| Fair Value: Due within Year 1 | 1,645 | 1,777 |
| Fair Value: Due Year 1-5 | 4,667 | 4,616 |
| AFS securities | 6,312 | 6,393 |
| State housing agency obligations: | ||
| AFS Securities | ||
| Amortized Cost: Due within Year 1 | 1 | |
| Amortized Cost: Due Year 1-5 | 2 | |
| Amortized Cost: Due Year 5-10 | 66 | 40 |
| Amortized Cost: Total | 67 | 42 |
| Fair Value: Due within Year 1 | 1 | |
| Fair Value: Due Year 1-5 | 2 | |
| Fair Value: Due Year 5-10 | 63 | 40 |
| AFS securities | 64 | 42 |
| MBS | ||
| AFS Securities | ||
| Amortized Cost: Total | 13,335 | 13,718 |
| AFS securities | $ 13,426 | $ 13,818 |
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amortized cost excluding accrued interest, before 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). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount excluding accrued interest, 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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- 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/disclosureRef
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