Financial Guarantees (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Dec. 31, 2025 |
|
| Financial Guarantees and Maximum Recovery [Line Items] | ||
| Contractual terms of our guarantees | 29 years | |
| Maximum Exposure | $ 11,253 | $ 11,380 |
| Guaranty Obligation | 101 | 96 |
| Maximum recovery | 4,224 | 4,319 |
| Unconsolidated Fannie Mae MBS | Unconsolidated VIEs | ||
| Financial Guarantees and Maximum Recovery [Line Items] | ||
| Maximum Exposure | 2,151 | 2,229 |
| Guaranty Obligation | 12 | 13 |
| Maximum recovery | 2,112 | 2,187 |
| Other guaranty arrangements | Unconsolidated VIEs | ||
| Financial Guarantees and Maximum Recovery [Line Items] | ||
| Maximum Exposure | 9,102 | 9,151 |
| Guaranty Obligation | 89 | 83 |
| Maximum recovery | 2,112 | 2,132 |
| Agency | Unconsolidated VIEs | ||
| Financial Guarantees and Maximum Recovery [Line Items] | ||
| Single security, Freddie Mac issued securities backing unconsolidated Fannie Mae securities | $ 181,200 | $ 184,300 |