Business Segments - Total Net Revenues and Pre-Tax Earnings By Geographic Region (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Net revenues	$ 15,388	$ 13,295	$ 33,092	$ 22,038
Pre-tax earnings	$ 6,840	$ 1,291	$ 15,177	$ 2,639
Percentage of total net revenues	100.00%	100.00%	100.00%	100.00%
Percentage of total pre-tax earnings	100.00%	100.00%	100.00%	100.00%
Americas [Member]
Segment Reporting Information [Line Items]
Net revenues	$ 9,957	$ 8,289	$ 20,782	$ 13,460
Pre-tax earnings	$ 4,465	$ 1,853	$ 9,480	$ 2,404
Percentage of total net revenues	65.00%	62.00%	63.00%	61.00%
Percentage of total pre-tax earnings	65.00%	143.00%	62.00%	91.00%
Europe, Middle East and Africa [Member]
Segment Reporting Information [Line Items]
Net revenues	$ 3,478	$ 3,453	$ 8,191	$ 5,561
Pre-tax earnings	$ 1,675	$ 566	$ 4,090	$ 1,002
Percentage of total net revenues	22.00%	26.00%	25.00%	25.00%
Percentage of total pre-tax earnings	25.00%	44.00%	27.00%	38.00%
Asia [Member]
Segment Reporting Information [Line Items]
Net revenues	$ 1,953	$ 1,553	$ 4,119	$ 3,017
Pre-tax earnings	$ 700	$ (1,128)	$ 1,607	$ (767)
Percentage of total net revenues	13.00%	12.00%	12.00%	14.00%
Percentage of total pre-tax earnings	10.00%	(87.00%)	11.00%	(29.00%)