Investments in Securities - Investments in Trading Securities (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Schedule of Investments in Trading Securities [Line Items] | ||
| Total trading securities | $ 55,895 | $ 69,514 |
| Total available-for-sale securities | 38,874 | 375 |
| Total investments in securities | 94,769 | 69,889 |
| Mortgage-related securities | ||
| Schedule of Investments in Trading Securities [Line Items] | ||
| Total trading securities | 16,216 | 14,291 |
| Amortized cost | 640 | 400 |
| Total available-for-sale securities | 609 | 375 |
| Non-mortgage-related securities | ||
| Schedule of Investments in Trading Securities [Line Items] | ||
| Total trading securities | 39,679 | 55,223 |
| Amortized cost | 38,500 | 0 |
| Total available-for-sale securities | 38,265 | 0 |
| Consolidated trusts | Mortgage-related securities | ||
| Schedule of Investments in Trading Securities [Line Items] | ||
| Total trading securities | $ 1,200 | $ 522 |
| 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/2009/role/commonPracticeRef
|
| X | ||||||||||
- 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
|
| X | ||||||||||
- 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
|
| 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of 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/disclosureRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|