Trading Assets and Liabilities (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014		Dec. 31, 2013
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading assets	$ 25,156		$ 28,894
Trading liabilities	8,815		10,875
U.S. Treasury [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading assets	2,717		1,344
US Government agency issued or guaranteed [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading assets	20		19
US Government sponsored enterprises [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading assets	115	[1]	159	[1]
Obligations of U.S. states and political subdivision [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading assets	27		25
Asset backed securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading assets	494		481
Corporate and foreign bonds [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading assets	6,931		9,099
Other securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading assets	21		25
Precious metals [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading assets	10,477		11,751
Trading liabilities	3,037		3,826
Derivatives [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading assets	4,354		5,991
Trading liabilities	5,007		6,741
Securities sold, not yet purchased [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading liabilities	$ 771		$ 308

[1] Includes mortgage backed securities of $88 million and $133 million issued or guaranteed by the Federal National Mortgage Association ("FNMA") and $27 million and $26 million issued or guaranteed by the Federal Home Loan Mortgage Corporation ("FHLMC") at June 30, 2014 and December 31, 2013, respectively.