Securities Financing Activities (Details) (USD $)	Mar. 31, 2012	Dec. 31, 2011
Components of collateralized financings [Abstract]
Securities purchased under resale agreements	$ 240,281,000,000	$ 235,000,000,000
Securities Borrowed	135,650,000,000	142,462,000,000
Securities sold under repurchase agreements	231,944,000,000	197,789,000,000
Securities loaned	17,253,000,000	14,214,000,000
Securities financing activities (Numeric) [Abstract]
Federal funds sold and securities purchased under resale agreements, at fair value	240,484,000,000	235,314,000,000
Federal funds purchased and securities loaned or sold under repurchase agreements, at fair value	250,483,000,000	213,532,000,000
Resale and repurchase agreements that have been netted	116,300,000,000	115,700,000,000
Fair value
Components of collateralized financings [Abstract]
Securities Borrowed	12,500,000,000	15,300,000,000
Securities financing activities (Numeric) [Abstract]
Federal funds sold and securities purchased under resale agreements, at fair value	26,300,000,000	24,900,000,000
Federal funds purchased and securities loaned or sold under repurchase agreements, at fair value	$ 13,200,000,000	$ 9,500,000,000