Offsetting Arrangements (Assets With Offsetting Arrangements) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014		Dec. 31, 2013
Offsetting Assets [Line Items]
Derivatives, Gross Amounts of Recognized Assets	$ 16,932		$ 11,977	[1]
Derivatives, Gross Amounts Offset in Statement of Condition	(8,220)	[2]	(6,501)	[2]
Net Amounts of Assets Presented in Statement of Condition	8,712		5,476
Resale Agreements and Securities Borrowing, Gross Amounts of Recognized Assets	48,078	[3]	48,221	[1],[3]
Resale Agreements and Securities Borrowing, Gross Amounts Offset in Statement of Condition	(29,692)	[2],[3]	(30,700)	[2],[3]
Net Amounts of Assets Presented in Statement of Condition	18,386	[3]	17,521	[3]
Total, Gross Amounts of Recognized Assets	65,010		60,198	[1]
Total, Gross Amounts Offset in Statement of Condition	(37,912)	[2]	(37,201)	[2]
Total, Net Amounts of Assets Presented in Statement of Condition	27,098		22,997
Securities purchased under resale agreements	2,603		6,230
Securities borrowed subject to master netting arrangements	15,783		11,291
Cash collateral netting
Offsetting Assets [Line Items]
Derivatives, Gross Amounts of Recognized Assets	0		0	[1]
Derivatives, Gross Amounts Offset in Statement of Condition	(841)	[2]	(1,928)	[2]
Net Amounts of Assets Presented in Statement of Condition	(841)		(1,928)
Interest-rate contracts
Offsetting Assets [Line Items]
Derivatives, Gross Amounts of Recognized Assets	63		65	[1]
Derivatives, Gross Amounts Offset in Statement of Condition	(34)	[2]	(59)	[2]
Net Amounts of Assets Presented in Statement of Condition	29		6
Foreign exchange contracts
Offsetting Assets [Line Items]
Derivatives, Gross Amounts of Recognized Assets	16,865		11,911	[1]
Derivatives, Gross Amounts Offset in Statement of Condition	(7,345)	[2]	(4,514)	[2]
Net Amounts of Assets Presented in Statement of Condition	9,520		7,397
Other derivative contracts
Offsetting Assets [Line Items]
Derivatives, Gross Amounts of Recognized Assets	4		1
Derivatives, Gross Amounts Offset in Statement of Condition	0		0
Net Amounts of Assets Presented in Statement of Condition	$ 4		$ 1

[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 $18,386 million as of September 30, 2014 were $2,603 million of resale agreements and $15,783 million of collateral provided related to securities borrowing. Included in the $17,521 million as of December 31, 2013 were $6,230 million of resale agreements and $11,291 million of collateral provided related to securities borrowing. Resale agreements and collateral provided related to securities borrowing were recorded in securities purchased under resale agreements and other assets, respectively, in our consolidated statement of condition. Refer to note 7 for additional information with respect to principal securities finance transactions.