Fair Value Option - Financial Assets and Financial Liabilities by Level (Detail) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Resale agreements	$ 182,502	$ 205,703
Securities borrowed	42,506	39,955
Customer and other receivables	25	42
Total financial assets at fair value	225,033	245,700
Deposits	(23,587)	(35,425)
Repurchase agreements	(159,690)	(165,883)
Securities loaned	(7,444)	(9,170)
Other secured financings	(14,240)	(17,074)
Unsecured borrowings: Short-term	(32,470)	(29,832)
Unsecured borrowings: Long-term	(65,358)	(52,390)
Other liabilities	(462)	(359)
Total financial liabilities at fair value	(303,251)	(310,133)
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Resale agreements	0	0
Securities borrowed	0	0
Customer and other receivables	0	0
Total financial assets at fair value	0	0
Deposits	0	0
Repurchase agreements	0	0
Securities loaned	0	0
Other secured financings	0	0
Unsecured borrowings: Short-term	0	0
Unsecured borrowings: Long-term	0	0
Other liabilities	0	0
Total financial liabilities at fair value	0	0
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Resale agreements	182,502	205,703
Securities borrowed	42,506	39,955
Customer and other receivables	25	42
Total financial assets at fair value	225,033	245,700
Deposits	(20,858)	(31,812)
Repurchase agreements	(159,690)	(165,883)
Securities loaned	(7,444)	(9,170)
Other secured financings	(12,370)	(14,508)
Unsecured borrowings: Short-term	(27,958)	(22,003)
Unsecured borrowings: Long-term	(55,685)	(42,977)
Other liabilities	(381)	(213)
Total financial liabilities at fair value	(284,386)	(286,566)
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Resale agreements	0	0
Securities borrowed	0	0
Customer and other receivables	0	0
Total financial assets at fair value	0	0
Deposits	(2,729)	(3,613)
Repurchase agreements	0	0
Securities loaned	0	0
Other secured financings	(1,870)	(2,566)
Unsecured borrowings: Short-term	(4,512)	(7,829)
Unsecured borrowings: Long-term	(9,673)	(9,413)
Other liabilities	(81)	(146)
Total financial liabilities at fair value	$ (18,865)	$ (23,567)