v3.26.1
Available-for-Sale Securities - Schedule Amortized Cost to Fair Value by Major Security Types and Other Income Activity from Grantor Trust (Details) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost $ 12,763,624 $ 12,377,325
Hedging Basis Adjustments, Amortized Cost (457,461) (363,915)
Gross Unrealized Gains 480,548 422,978
Hedging Basis Adjustments, Gross Unrealized Gains 457,461 363,915
Gross Unrealized Losses (524,041) (454,458)
Fair Value 12,720,131 12,345,845
Housing and U.S. obligations    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 2,221,048 2,223,460
Gross Unrealized Gains 1,472 2,599
Gross Unrealized Losses (4,978) (1,264)
Fair Value 2,217,542 2,224,795
MBS AFS Before Hedging Adjustments    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 11,000,037 10,517,780
Gross Unrealized Gains 21,615 56,464
Gross Unrealized Losses (519,063) (453,194)
Fair Value 10,502,589 10,121,050
Total Floating    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 270,233 293,613
Gross Unrealized Gains 727 593
Gross Unrealized Losses (745) (1,402)
Fair Value 270,215 292,804
CMO    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 267,848 291,061
Gross Unrealized Gains 652 509
Gross Unrealized Losses (745) (1,402)
Fair Value 267,755 290,168
Pass-through    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 2,385 2,552
Gross Unrealized Gains 75 84
Gross Unrealized Losses 0 0
Fair Value 2,460 2,636
Asset-Backed Securities, Fixed    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 10,729,804 10,224,167
Gross Unrealized Gains 20,888 55,871
Gross Unrealized Losses (518,318) (451,792)
Fair Value 10,232,374 9,828,246
CMBS    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 10,729,804 10,224,167
Gross Unrealized Gains 20,888 55,871
Gross Unrealized Losses (518,318) (451,792)
Fair Value 10,232,374 9,828,246
Mortgage-backed securities    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 10,542,576 10,153,865
Gross Unrealized Gains 479,076 420,379
Gross Unrealized Losses (519,063) (453,194)
Fair Value $ 10,502,589 $ 10,121,050