v3.26.1
Securitization Activities and Consolidation - Non-Consolidated VIEs (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Assets [Abstract]    
Investment securities, at fair value $ 84,342 $ 85,412
Other Assets 26,628 26,566
Assets 3,518,315 3,497,598
Outstanding balance of the guarantor advance 300 400
Liabilities [Abstract]    
Other Liabilities 11,199 11,595
Variable Interest Entity, Not Primary Beneficiary    
Assets [Abstract]    
Investment securities, at fair value 10,471 12,006
Other Assets 4,792 5,257
Assets 465,228 487,914
Maximum Exposure to Loss 403,538 422,902
Liabilities [Abstract]    
Other Liabilities 4,739 5,120
Variable Interest Entity, Not Primary Beneficiary | Other    
Assets [Abstract]    
Investment securities, at fair value 0 0
Other Assets 6 7
Assets 59 64
Maximum Exposure to Loss 13 15
Liabilities [Abstract]    
Other Liabilities 0 0
Variable Interest Entity, Not Primary Beneficiary | Single Family Guarantee Segment    
Assets [Abstract]    
Investment securities, at fair value 6,899 6,954
Other Assets 344 333
Assets 147,465 152,832
Maximum Exposure to Loss 119,665 123,364
Liabilities [Abstract]    
Other Liabilities 1,306 1,307
Variable Interest Entity, Not Primary Beneficiary | Single Family Guarantee Segment | Securitization products    
Assets [Abstract]    
Investment securities, at fair value 1,378 1,451
Other Assets 154 162
Assets 28,936 30,025
Maximum Exposure to Loss 23,731 24,604
Liabilities [Abstract]    
Other Liabilities 483 498
Variable Interest Entity, Not Primary Beneficiary | Single Family Guarantee Segment | Guarantees of Fannie Mae securities    
Assets [Abstract]    
Investment securities, at fair value 5,521 5,503
Other Assets 91 74
Assets 95,575 98,370
Maximum Exposure to Loss 95,930 98,754
Liabilities [Abstract]    
Other Liabilities 737 675
Variable Interest Entity, Not Primary Beneficiary | Single Family Guarantee Segment | CRT products    
Assets [Abstract]    
Investment securities, at fair value 0 0
Other Assets 99 97
Assets 22,954 24,437
Maximum Exposure to Loss 4 6
Liabilities [Abstract]    
Other Liabilities 86 134
Variable Interest Entity, Not Primary Beneficiary | Multifamily    
Assets [Abstract]    
Investment securities, at fair value 3,572 5,052
Other Assets 4,442 4,917
Assets 317,704 335,018
Maximum Exposure to Loss 283,860 299,523
Liabilities [Abstract]    
Other Liabilities 3,433 3,813
Variable Interest Entity, Not Primary Beneficiary | Multifamily | Securitization products    
Assets [Abstract]    
Investment securities, at fair value 3,572 5,052
Other Assets 4,394 4,886
Assets 314,464 332,572
Maximum Exposure to Loss 283,834 299,507
Liabilities [Abstract]    
Other Liabilities 3,413 3,792
Variable Interest Entity, Not Primary Beneficiary | Multifamily | CRT products    
Assets [Abstract]    
Investment securities, at fair value 0 0
Other Assets 48 31
Assets 3,240 2,446
Maximum Exposure to Loss 26 16
Liabilities [Abstract]    
Other Liabilities $ 20 $ 21