Derivative Financial Instruments (Impact Of Derivatives On Consolidated Statement Of Income) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Derivative [Line Items]
Losses on written options recorded in other expense			$ 0		$ 5
Derivatives not designated as hedging instruments [Member]
Derivative [Line Items]
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	494	[1]	669	[1]	631	[1]
Derivatives designated as fair value hedges [Member]
Derivative [Line Items]
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	95		(251)		14
Amount of Gain (Loss) on Hedged Item Recognized in Consolidated Statement of Income	(96)		244		(9)
Foreign exchange contracts [Member] | Trading services [Member] | Derivatives not designated as hedging instruments [Member]
Derivative [Line Items]
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	576	[1]	641	[1]	618	[1]
Foreign exchange contracts [Member] | Processing fees and other revenue [Member] | Derivatives not designated as hedging instruments [Member]
Derivative [Line Items]
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	(2)	[1]	7	[1]	(4)	[1]
Foreign exchange contracts [Member] | Processing fees and other revenue [Member] | Contract three [Member] | Derivatives designated as fair value hedges [Member]
Derivative [Line Items]
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	34		(161)		0
Foreign exchange contracts [Member] | Processing fees and other revenue [Member] | Investment securities [Member] | Derivatives designated as fair value hedges [Member]
Derivative [Line Items]
Amount of Gain (Loss) on Hedged Item Recognized in Consolidated Statement of Income	(34)		161		0
Interest rate contracts [Member] | Trading services [Member] | Derivatives not designated as hedging instruments [Member]
Derivative [Line Items]
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	(86)	[1]	21	[1]	7	[1]
Interest rate contracts [Member] | Processing fees and other revenue [Member] | Derivatives not designated as hedging instruments [Member]
Derivative [Line Items]
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	6	[1]	0	[1]	10	[1]
Interest rate contracts [Member] | Processing fees and other revenue [Member] | Contract one [Member] | Derivatives designated as fair value hedges [Member]
Derivative [Line Items]
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	50		75		57
Interest rate contracts [Member] | Processing fees and other revenue [Member] | Contract two [Member] | Derivatives designated as fair value hedges [Member]
Derivative [Line Items]
Amount of Gain (Loss) on Derivative Recognized in Consolidated Statement of Income	11		(165)		(43)
Interest rate contracts [Member] | Processing fees and other revenue [Member] | Long-term debt [Member] | Derivatives designated as fair value hedges [Member]
Derivative [Line Items]
Amount of Gain (Loss) on Hedged Item Recognized in Consolidated Statement of Income	(45)		(70)		(49)
Interest rate contracts [Member] | Processing fees and other revenue [Member] | Investment securities available for sale [Member] | Derivatives designated as fair value hedges [Member]
Derivative [Line Items]
Amount of Gain (Loss) on Hedged Item Recognized in Consolidated Statement of Income	$ (17)		$ 153		$ 40

[1] Losses on derivatives related to book-value protection provided to stable value funds are recorded in other expenses, and totaled approximately $5 million for the year ended December 31, 2010. There were no losses related to stable value funds for the years ended December 31, 2012 and 2011.