Securities Financing Activities, Gross Obligations by Underlying Collateral Type (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase agreements	$ 415,997	$ 322,482
Securities lending arrangements	10,143	7,558
Total repurchases and securities lending	426,140	330,040
Securities of U.S. Treasury and federal agencies [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase agreements	262,132	176,386
Federal agency mortgage-backed securities [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase agreements	123,015	118,503
Non-agency mortgage-backed securities [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase agreements	4,512	3,266
Corporate debt securities [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase agreements	16,629	13,567
Securities lending arrangements	2,233	1,735
Asset-backed securities [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase agreements	3,424	4,705
Equity securities [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase agreements	3,077	2,809
Securities lending arrangements	7,793	5,700
Other [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Repurchase agreements	3,208	3,246
Securities lending arrangements	$ 117	$ 123