v3.26.1
Available-for-sale Securities (Redemption Terms) (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
ScheduleOfAvailableForSaleSecuritiesTable [Line Items]    
Available-for-Sale, Estimated Fair Value $ 13,816 $ 8,933
Available-for-sale securities, amortized cost [1] 13,787 8,908
Available-for-Sale, Accrued Interest Receivable   57
US Treasury Securities [Member]    
ScheduleOfAvailableForSaleSecuritiesTable [Line Items]    
Due in one year or less, Amortized Cost [1] 2,224 1,229
Due in one year or less, Fair Value 2,225 1,230
Due after one year through five years, estimated fair value 3,820 4,364
Due after one year through five years, amortized cost [1] 3,810 4,352
Available-for-Sale, Estimated Fair Value 6,045 5,594
Available-for-sale securities, amortized cost [1] 6,034 5,581
Non-mortgage backed securities [Member]    
ScheduleOfAvailableForSaleSecuritiesTable [Line Items]    
Available-for-Sale, Estimated Fair Value 6,045 5,594
Available-for-sale securities, amortized cost [1] 6,034 5,581
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]    
ScheduleOfAvailableForSaleSecuritiesTable [Line Items]    
Available-for-Sale, Estimated Fair Value [2] 7,771 3,339
Available-for-sale securities, amortized cost [1],[2] $ 7,753 $ 3,327
[1] Amortized cost includes adjustments made to the cost basis for accretion, amortization, fair value hedge accounting adjustments, and excludes accrued interest receivable of $78 and $57 as of June 30, 2026 and December 31, 2025, respectively.
[2] Mortgage-backed securities (MBS) are not presented by contractual maturity because their actual maturities may differ from contractual maturities as borrowers may have the right to call or prepay obligations with or without call or prepayment fees.