v3.26.1
Available-for-Sale Securities (Details) - USD ($)
$ in Thousands
Mar. 31, 2026
Dec. 31, 2025
Debt Securities, Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract]    
Debt Securities, Available-for-sale, Amortized Cost $ 18,745,712 $ 19,125,045
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax 186,541 185,891
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax 3,422 2,744
Available-for-sale securities [1] 18,928,831 19,308,192
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 3,422  
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-sale, Amortized Cost 18,745,712 19,125,045
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax 186,541 185,891
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax 3,422 2,744
Available-for-sale securities [1] 18,928,831 19,308,192
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 3,422  
US Government-sponsored Enterprises Debt Securities [Member]    
Debt Securities, Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract]    
Debt Securities, Available-for-sale, Amortized Cost 1,404,032 1,489,642
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax 6,489 9,189
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax 0 0
Available-for-sale securities 1,410,521 1,498,831
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-sale, Amortized Cost 1,404,032 1,489,642
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax 6,489 9,189
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax 0 0
Available-for-sale securities 1,410,521 1,498,831
Non-mortgage-backed securities [Member]    
Debt Securities, Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract]    
Debt Securities, Available-for-sale, Amortized Cost 1,404,032 1,489,642
Available-for-sale securities 1,410,521 1,498,831
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Amortized Cost 1,113,659 1,035,186
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Amortized Cost 290,373 440,776
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after Five Through Ten Years, Amortized Cost 0 13,680
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value 1,115,739 1,037,965
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Fair Value 294,782 446,564
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after Five Through Ten Years, Fair Value 0 14,302
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-sale, Amortized Cost 1,404,032 1,489,642
Available-for-sale securities 1,410,521 1,498,831
Available-for-sale Securities, Debt Maturities [Abstract]    
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Amortized Cost 1,113,659 1,035,186
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Amortized Cost 290,373 440,776
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after Five Through Ten Years, Amortized Cost 0 13,680
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value 1,115,739 1,037,965
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Fair Value 294,782 446,564
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after Five Through Ten Years, Fair Value 0 14,302
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Multifamily [Member]    
Debt Securities, Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract]    
Debt Securities, Available-for-sale, Amortized Cost 17,341,680 17,635,403
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax 180,052 176,702
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax 3,422 2,744
Available-for-sale securities 17,518,310 17,809,361
Debt Securities, Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value 673,894 207,012
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 1,400 636
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 127,776 88,049
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 2,022 2,108
Debt Securities, Available-for-sale, Unrealized Loss Position 801,670 295,061
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 3,422 2,744
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-sale, Amortized Cost 17,341,680 17,635,403
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax 180,052 176,702
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax 3,422 2,744
Available-for-sale securities 17,518,310 17,809,361
Debt Securities, Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value 673,894 207,012
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 1,400 636
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer 127,776 88,049
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 2,022 2,108
Debt Securities, Available-for-sale, Unrealized Loss Position 801,670 295,061
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss 3,422 2,744
Other Liabilities    
Debt Securities, Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract]    
Available-for-sale securities   818,975
Debt Securities, Available-for-sale [Line Items]    
Available-for-sale securities   818,975
Categories of Investments, Marketable Securities, Available-for-sale Securities [Member]    
Debt Securities, Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract]    
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss 71,114 66,897
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss $ 71,114 $ 66,897
[1] Amortized cost: $18,745,712 and $19,125,045 at March 31, 2026 and December 31, 2025, respectively.