Commitments And Contingencies (Contractual Amounts Of Credit-Related Off-Balance Sheet Financial Instruments) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011		Dec. 31, 2010
Commitments And Contingencies [Abstract]
Indemnified securities financing	$ 302,342	[1]	$ 334,235	[1]
Unfunded commitments to extend credit	17,297		14,772
Asset purchase agreements	5,056		4,866
Standby letters of credit	$ 3,938		$ 4,174

[1] Related collateral and other information is provided in the following "Securities Finance" section.