Fair Value (Level 3 Total Realized And Unrealized Gains And Losses Recorded In Revenue) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Total Revenue [Member]
Realized and Unrealized Gains and Losses [Line Items]
Total Realized and Unrealized Gains (Losses) Recorded in Revenue	$ 17	$ 49
Change in Unrealized Gains (Losses) Related to Financial Instruments Held	(2)	14
Trading services
Realized and Unrealized Gains and Losses [Line Items]
Total Realized and Unrealized Gains (Losses) Recorded in Revenue	(1)	34
Change in Unrealized Gains (Losses) Related to Financial Instruments Held	(2)	14
Total fee revenue
Realized and Unrealized Gains and Losses [Line Items]
Total Realized and Unrealized Gains (Losses) Recorded in Revenue	(1)	34
Change in Unrealized Gains (Losses) Related to Financial Instruments Held	(2)	14
Net interest revenue
Realized and Unrealized Gains and Losses [Line Items]
Total Realized and Unrealized Gains (Losses) Recorded in Revenue	18	15
Change in Unrealized Gains (Losses) Related to Financial Instruments Held	$ 0	$ 0