v3.26.1
Mortgage-Backed Securities - Schedule of Components of Carrying Value of MBS and GSE CRT Portfolio (Details) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]    
Principal/ Notional Balance $ 7,354,216 $ 6,606,785
Unamortized premium 41,444 39,890
Unamortized discount (503,083) (504,008)
Gross unrealized gains 84,318 139,370
Gross unrealized losses (26,986) (5,428)
Total 6,949,909 6,276,609
MBS    
Debt Securities, Available-for-sale [Line Items]    
Principal/ Notional Balance 6,890,694 6,121,811
Unamortized premium 41,444 39,890
Unamortized discount (96,579) (79,603)
Gross unrealized gains 76,848 130,576
Gross unrealized losses (26,884) (5,385)
Total 6,885,523 6,207,289
Interest-Only Securities    
Debt Securities, Available-for-sale [Line Items]    
Principal/ Notional Balance 463,522 484,974
Unamortized premium 0 0
Unamortized discount (406,504) (424,405)
Gross unrealized gains 7,470 8,794
Gross unrealized losses (102) (43)
Total $ 64,386 $ 69,320