v3.26.1
Derivatives and Hedging Activities Derivative Notional Amounts (Details) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Derivatives, Fair Value [Line Items]    
Notional amount of derivatives $ 68,159,282 $ 72,165,385
Estimated fair value of derivative assets 426,702 389,867
Estimated fair value of derivative liabilities 497,164 552,668
Netting adjustments and cash collateral, derivative asset [1],[2] 32,044 55,624
Netting adjustments and cash collateral, derivative liability [1],[2] (493,790) (551,733)
Derivative Asset, Total 458,746 445,491
Derivative Liability, Total 3,374 935
Cash collateral pledged to counterparties 668,506 719,187
Cash collateral received from counterparties 142,672 111,829
Derivatives designated as hedging instruments | Interest-rate swaps    
Derivatives, Fair Value [Line Items]    
Notional amount of derivatives 63,143,899 64,976,941
Estimated fair value of derivative assets 425,690 389,237
Estimated fair value of derivative liabilities 495,919 552,430
Derivatives not designated as hedging instruments    
Derivatives, Fair Value [Line Items]    
Notional amount of derivatives 5,015,383 7,188,444
Estimated fair value of derivative assets 1,012 630
Estimated fair value of derivative liabilities 1,245 238
Derivatives not designated as hedging instruments | Interest-rate swaps    
Derivatives, Fair Value [Line Items]    
Notional amount of derivatives 4,170,000 6,336,000
Estimated fair value of derivative assets 323 280
Estimated fair value of derivative liabilities 52 0
Derivatives not designated as hedging instruments | Swaptions    
Derivatives, Fair Value [Line Items]    
Notional amount of derivatives 50,000 400,000
Estimated fair value of derivative assets 94 30
Estimated fair value of derivative liabilities 0 0
Derivatives not designated as hedging instruments | Interest-rate caps/floors    
Derivatives, Fair Value [Line Items]    
Notional amount of derivatives 331,100 331,100
Estimated fair value of derivative assets 298 224
Estimated fair value of derivative liabilities 0 0
Derivatives not designated as hedging instruments | Interest-rate forwards    
Derivatives, Fair Value [Line Items]    
Notional amount of derivatives 231,600 62,100
Estimated fair value of derivative assets 17 0
Estimated fair value of derivative liabilities 1,084 234
MDCs | Derivatives not designated as hedging instruments | Interest-rate forwards    
Derivatives, Fair Value [Line Items]    
Notional amount of derivatives 232,683 59,244
Estimated fair value of derivative assets 280 96
Estimated fair value of derivative liabilities $ 109 $ 4
[1] Represents the application of the netting requirements that allow us to settle (i) positive and negative positions and (ii) cash collateral and related accrued interest held or placed with the same clearing agent and/or counterparty. Cash collateral pledged to counterparties at June 30, 2026 and December 31, 2025, including accrued interest, totaled $668,506 and $719,187, respectively. Cash collateral received from counterparties and held at June 30, 2026 and December 31, 2025, including accrued interest, totaled $142,672 and $111,829, respectively.
[2] Represents the application of the netting requirements that allow us to settle (i) positive and negative positions and (ii) cash collateral and related accrued interest held or placed with the same clearing agent and/or counterparty.