Business Segments - Net Revenues and Pre-Tax Earnings for Each Geographic Region (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Net revenues	$ 8,168	$ 6,861	$ 22,438	$ 26,547
Pre-tax earnings	$ 2,868	$ 2,046	$ 6,907	$ 7,706
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	$ 4,695	$ 3,838	$ 13,395	$ 14,851
Pre-tax earnings	$ 1,609	$ 1,022	$ 4,099	$ 3,458
Percentage of total net revenues	58.00%	56.00%	60.00%	56.00%
Percentage of total pre-tax earnings	56.00%	50.00%	59.00%	44.00%
Europe, Middle East and Africa [Member]
Segment Reporting Information [Line Items]
Net revenues	$ 2,079	$ 2,042	$ 5,937	$ 7,157
Pre-tax earnings	$ 716	$ 712	$ 1,861	$ 2,525
Percentage of total net revenues	25.00%	30.00%	26.00%	27.00%
Percentage of total pre-tax earnings	25.00%	34.00%	27.00%	33.00%
Asia [Member]
Segment Reporting Information [Line Items]
Net revenues	$ 1,394	$ 981	$ 3,106	$ 4,539
Pre-tax earnings	$ 543	$ 337	$ 947	$ 1,748
Percentage of total net revenues	17.00%	14.00%	14.00%	17.00%
Percentage of total pre-tax earnings	19.00%	16.00%	14.00%	23.00%