v3.26.1
Available-for-Sale Securities - Schedule of Interest Rate Payment Terms of Investments in Mortgage-backed Securities and State And Local Housing Finance Agency Obligations Classified as AFS Securities (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
Fair Value 12,720,131 12,345,845
Mortgage-backed securities    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 10,542,576 10,153,865
Fair Value 10,502,589 10,121,050
Total Floating    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 270,233 293,613
Fair Value 270,215 292,804
CMO    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 267,848 291,061
Fair Value 267,755 290,168
Pass-through    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 2,385 2,552
Fair Value 2,460 2,636
Total Fixed    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 10,272,343 9,860,252
Fair Value 10,232,374 9,828,246
CMBS    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 10,272,343 9,860,252
Fair Value 10,232,374 9,828,246
Housing and U.S. Obligations, Floating    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 1,664,730 1,665,775
Fair Value 1,666,174 1,664,523
Housing and U.S. Obligations, Fixed    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 556,318 557,685
Fair Value $ 551,368 $ 560,272