v3.25.2
Concentration of Credit and Other Risks - Concentration of Credit Risk - Multifamily Mortgage Portfolio (Details)(Details)
$ in Millions
Jun. 30, 2025
USD ($)
Concentration Risk [Line Items]  
Multifamily Delinquency Rate 0.47%
Northeast  
Concentration Risk [Line Items]  
Multifamily Delinquency Rate 0.91%
West  
Concentration Risk [Line Items]  
Multifamily Delinquency Rate 0.21%
Southeast  
Concentration Risk [Line Items]  
Multifamily Delinquency Rate 0.21%
Southwest  
Concentration Risk [Line Items]  
Multifamily Delinquency Rate 0.42%
North Central  
Concentration Risk [Line Items]  
Multifamily Delinquency Rate 0.69%
California  
Concentration Risk [Line Items]  
Multifamily Delinquency Rate 0.31%
Texas  
Concentration Risk [Line Items]  
Multifamily Delinquency Rate 0.50%
Florida  
Concentration Risk [Line Items]  
Multifamily Delinquency Rate 0.16%
New York  
Concentration Risk [Line Items]  
Multifamily Delinquency Rate 2.33%
GEORGIA  
Concentration Risk [Line Items]  
Multifamily Delinquency Rate 0.23%
All Other  
Concentration Risk [Line Items]  
Multifamily Delinquency Rate 0.30%
Geographic Concentration Risk | All Other  
Concentration Risk [Line Items]  
Portfolio UPB $ 1,922,277
Unpaid Principal Balance, Percent Of Portfolio 61.00%
Geographic Concentration Risk | Multifamily Unpaid Principal Balance [Member]  
Concentration Risk [Line Items]  
Portfolio UPB $ 466,219
Unpaid Principal Balance, Percent Of Portfolio 100.00%
Geographic Concentration Risk | Multifamily Unpaid Principal Balance [Member] | Northeast  
Concentration Risk [Line Items]  
Portfolio UPB $ 116,404
Unpaid Principal Balance, Percent Of Portfolio 25.00%
Geographic Concentration Risk | Multifamily Unpaid Principal Balance [Member] | West  
Concentration Risk [Line Items]  
Portfolio UPB $ 111,932
Unpaid Principal Balance, Percent Of Portfolio 24.00%
Geographic Concentration Risk | Multifamily Unpaid Principal Balance [Member] | Southeast  
Concentration Risk [Line Items]  
Portfolio UPB $ 95,789
Unpaid Principal Balance, Percent Of Portfolio 21.00%
Geographic Concentration Risk | Multifamily Unpaid Principal Balance [Member] | Southwest  
Concentration Risk [Line Items]  
Portfolio UPB $ 94,574
Unpaid Principal Balance, Percent Of Portfolio 20.00%
Geographic Concentration Risk | Multifamily Unpaid Principal Balance [Member] | North Central  
Concentration Risk [Line Items]  
Portfolio UPB $ 47,520
Unpaid Principal Balance, Percent Of Portfolio 10.00%
Geographic Concentration Risk | Multifamily Unpaid Principal Balance [Member] | California  
Concentration Risk [Line Items]  
Portfolio UPB $ 60,264
Unpaid Principal Balance, Percent Of Portfolio 13.00%
Geographic Concentration Risk | Multifamily Unpaid Principal Balance [Member] | Texas  
Concentration Risk [Line Items]  
Portfolio UPB $ 59,297
Unpaid Principal Balance, Percent Of Portfolio 13.00%
Geographic Concentration Risk | Multifamily Unpaid Principal Balance [Member] | Florida  
Concentration Risk [Line Items]  
Portfolio UPB $ 40,444
Unpaid Principal Balance, Percent Of Portfolio 9.00%
Geographic Concentration Risk | Multifamily Unpaid Principal Balance [Member] | New York  
Concentration Risk [Line Items]  
Portfolio UPB $ 36,997
Unpaid Principal Balance, Percent Of Portfolio 8.00%
Geographic Concentration Risk | Multifamily Unpaid Principal Balance [Member] | GEORGIA  
Concentration Risk [Line Items]  
Portfolio UPB $ 19,591
Unpaid Principal Balance, Percent Of Portfolio 4.00%
Geographic Concentration Risk | Multifamily Unpaid Principal Balance [Member] | All Other  
Concentration Risk [Line Items]  
Portfolio UPB $ 249,626
Unpaid Principal Balance, Percent Of Portfolio 53.00%