Collateralized Agreements and Financings - Schedule of Gross Carrying Value of Repurchase Agreements and Securities Loaned by Class of Collateral Pledged (Detail) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Offsetting Liabilities [Line Items]
Repurchase agreements	$ 502,148	$ 408,242
Securities loaned	71,581	66,674
Money market instruments
Offsetting Liabilities [Line Items]
Repurchase agreements	395	61
Securities loaned	0	0
U.S. government and agency obligations
Offsetting Liabilities [Line Items]
Repurchase agreements	319,406	276,341
Securities loaned	0	0
Non-U.S. government obligations
Offsetting Liabilities [Line Items]
Repurchase agreements	141,625	95,812
Securities loaned	1,416	461
Securities backed by commercial real estate
Offsetting Liabilities [Line Items]
Repurchase agreements	247	407
Securities loaned	0	0
Securities backed by residential real estate
Offsetting Liabilities [Line Items]
Repurchase agreements	2,219	1,154
Securities loaned	0	0
Corporate debt securities
Offsetting Liabilities [Line Items]
Repurchase agreements	13,281	11,521
Securities loaned	186	376
State and municipal obligations
Offsetting Liabilities [Line Items]
Repurchase agreements	370	573
Securities loaned	0	0
Other debt obligations
Offsetting Liabilities [Line Items]
Repurchase agreements	89	289
Securities loaned	0	0
Equity securities
Offsetting Liabilities [Line Items]
Repurchase agreements	24,516	22,084
Securities loaned	$ 69,979	$ 65,837