v3.26.1
Investments (AFS Contractual Maturity) (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-Sale, Excluding Accrued Interest $ 28,775 $ 27,519
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss 28,478 27,336
Non-mortgage-backed securities [Member]    
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Amortized Cost 357 399
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after Five Through Ten Years, Amortized Cost 349 224
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Amortized Cost 2 11
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value 2 11
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Amortized Cost 44 47
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Fair Value 46 49
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after Five Through Ten Years, Fair Value 355 227
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value 378 426
Debt Securities, Available-for-Sale, Excluding Accrued Interest 781 713
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss 752 681
Mortgage-backed securities [Member]    
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-sale 27,994 26,806
Debt Securities, Available-for-sale, Amortized Cost 27,726 26,655
Debt Securities, Available-for-Sale, Excluding Accrued Interest $ 27,994 $ 26,806