Offsetting Arrangements (Liabilities With Offsetting Arrangements) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities	$ 10,577	[1]	$ 9,438	[1]
Gross Amounts Offset in Statement of Condition	(4,270)	[1]	(4,071)	[1],[2]
Net Amounts of Liabilities Presented in Statement of Condition	6,307	[1]	5,367	[1]
Gross Amounts of Recognized Liabilities	46,488	[1],[3]	36,801	[1],[3]
Gross Amounts Offset in Statement of Condition	(29,974)	[2],[3]	(23,809)	[2],[3]
Net Amounts of Liabilities Presented in Statement of Condition	16,514	[3]	12,992	[3]
Gross Amounts of Recognized Liabilities	57,065	[1]	46,239	[1]
Gross Amounts Offset in Statement of Condition	(34,244)	[2]	(27,880)	[2]
Total, Net Amount of Liabilities Presented in Statement of Condition	22,821		18,359
Securities sold under repurchase agreements	10,123		8,006
Securities Lending, Fair Value, Amount Not Offset Against Collateral	6,391		4,986
Interest-rate contracts
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities	307	[1]	345	[1]
Gross Amounts Offset in Statement of Condition	(45)	[2]	(19)	[2]
Net Amounts of Liabilities Presented in Statement of Condition	262		326
Foreign exchange contracts
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities	10,261	[1]	9,084	[1]
Gross Amounts Offset in Statement of Condition	(3,757)	[2]	(3,574)	[2]
Net Amounts of Liabilities Presented in Statement of Condition	6,504		5,510
Other derivative contracts
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities	9	[1]	9	[1]
Gross Amounts Offset in Statement of Condition	0	[2]	0	[2]
Net Amounts of Liabilities Presented in Statement of Condition	9		9
Cash collateral netting
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities	0	[1]	0	[1]
Gross Amounts Offset in Statement of Condition	(468)	[2]	(478)	[2]
Net Amounts of Liabilities Presented in Statement of Condition	$ (468)		$ (478)

[1] Amounts include all transactions regardless of whether or not they are subject to an enforceable netting arrangement.

[2] Amounts subject to netting arrangements which have been determined to be legally enforceable.

[3] Included in the $16,514 million as of September 30, 2013 was $10,123 million of repurchase agreements and $6,391 million of collateral related to securities lending. Included in the $12,992 million as of December 31, 2012 was $8,006 million of repurchase agreements and $4,986 million of collateral related to securities lending. Repurchase agreements and collateral related to securities lending were recorded in securities sold under repurchase agreements and accrued expenses and other liabilities, respectively, in our consolidated statement of condition. Refer to note 8 for additional information with respect to principal securities finance transactions.