Offsetting Arrangements Assets With Offsetting Arrangements (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013		Dec. 31, 2012
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets	$ 6,110	[1]	$ 5,478	[1]
Gross Amounts Offset in Statement of Condition	(5,788)	[1]	(5,045)	[1]
Net Amounts of Assets Presented in Statement of Condition	322	[1],[2]	433	[1],[2]
Gross Amounts of Recognized Assets	45,060	[3]	34,853	[3]
Gross Amounts Offset in Statement of Condition	(27,266)	[3]	(23,005)	[3]
Net Amounts of Assets Presented in Statement of Condition	17,794	[3],[4]	11,848	[3],[4]
Gross Amounts of Recognized Assets	51,170		40,331
Gross Amounts Offset in Statement of Condition	33,054		28,050
Net Amounts of Assets Presented in Statement of Condition	18,116		12,281
Derivative assets not subject to netting arrangements	4,189		4,123
Securities for reverse repurchase agreements subject to master netting arrangements	8,703		5,016
Securities borrowed subject to master netting arrangements	9,091		6,832
Cross product and cash collateral netting
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets	0		0
Gross Amounts Offset in Statement of Condition	(2,209)		(1,451)
Net Amounts of Assets Presented in Statement of Condition	(2,209)		(1,451)
Interest-rate contracts
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets	86		223
Gross Amounts Offset in Statement of Condition	(12)		(19)
Net Amounts of Assets Presented in Statement of Condition	74		204
Foreign exchange contracts
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets	6,024		5,255
Gross Amounts Offset in Statement of Condition	(3,567)		(3,575)
Net Amounts of Assets Presented in Statement of Condition	$ 2,457		$ 1,680

[1] In addition to the $322 million and $433 million as of March 31, 2013 and December 31, 2012, respectively. we have $4,189 million and $4,123 million, respectively, of derivative assets not determined to be subject to enforceable netting arrangements. Refer to notes 2 and 10 for additional information with respect to derivative financial instrument balances recorded in our consolidated statement of condition.

[2] Excludes the impact of non-cash collateral of $42 million and $105 million as of March 31, 2013 and December 31, 2012, respectively.

[3] Included in the $17,794 million as of March 31, 2013 was $8,703 million of resale agreements and $9,091 million of securities borrowing. Included in the $11,848 million as of December 31, 2012 was $5,016 million of resale agreements and $6,832 million of securities borrowing. Resale agreements and securities borrowing were recorded in securities purchased under resale agreements and other assets, respectively, in our consolidated statement of condition. Refer to notes 6 and 7 for additional information with respect to these arrangements.

[4] Excludes the impact of non-cash collateral. These secured financing transactions are fully collateralized.