Segment and Geographic Information (Net Interest by Segments) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Interest income									$ 5,725	[1]	$ 7,258	[1]	$ 7,305	[1]
Interest expense									5,924	[1]	6,902	[1]	6,407	[1]
Net interest	175	(155)	(160)	(59)	270	145	(66)	7	(199)		356		898
Institutional Securities
Interest income									4,128		5,740		5,910
Interest expense									5,914		6,820		6,136
Net interest									(1,786)		(1,080)		(226)
Global Wealth Management Group
Interest income									2,015		1,863		1,581
Interest expense									403		386		465
Net interest									1,612		1,477		1,116
Asset Management
Interest income									10		10		22
Interest expense									34		51		98
Net interest									(24)		(41)		(76)
Intersegment Eliminations
Interest income									(428)		(355)		(208)
Interest expense									(427)		(355)		(292)
Net interest									$ (1)		$ 0		$ 84

[1] Interest income and expense are recorded within the consolidated statements of income depending on the nature of the instrument and related market conventions. When interest is included as a component of the instrument’s fair value, interest is included within Principal transactions—Trading revenues or Principal transactions—Investments revenues. Otherwise, it is included within Interest income or Interest expense.