Collateralized Transactions - Offsetting of Certain Collateralized Transactions (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Securities purchased under agreements to resell
Gross Amounts	$ 480,516	$ 409,635
Amounts Offset	(368,782)	(291,070)
Balance Sheet Net Amounts	111,734	118,565
Amounts not offset	(109,259)	(116,157)
Net Amounts	2,475	2,408
Securities borrowed
Gross Amounts	200,015	165,642
Amounts Offset	(70,902)	(41,783)
Balance Sheet Net Amounts	129,113	123,859
Amounts not offset	(125,492)	(117,573)
Net Amounts	3,621	6,286
Securities sold under agreements to repurchase
Gross Amounts	430,286	341,137
Amounts Offset	(368,782)	(291,070)
Balance Sheet Net Amounts	61,504	50,067
Amounts not offset	(56,918)	(45,520)
Net Amounts	4,586	4,547
Securities loaned
Gross Amounts	86,846	57,009
Amounts Offset	(70,902)	(41,783)
Balance Sheet Net Amounts	15,944	15,226
Amounts not offset	(15,839)	(15,211)
Net Amounts	105	15
Net amounts for which master netting agreements are not in place or may not be legally enforceable
Securities purchased under agreements to resell	886	2,054
Securities borrowed	80	2,079
Securities sold under agreements to repurchase	$ 3,285	$ 3,448

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