Goodwill and Other Intangibles, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Goodwill [Line Items]
Goodwill acquired during period	$ 0	$ 0
Impairment of goodwill	0	0	$ 142
Goodwill	1,792	1,792
Balance Sheet Management
Goodwill [Line Items]
Goodwill, Impaired, Accumulated Impairment Loss	101
Trading And Investing
Goodwill [Line Items]
Goodwill, Impaired, Accumulated Impairment Loss	142
Trading And Investing | Market Making Reporting Unit
Goodwill [Line Items]
Impairment of goodwill			142
Trading And Investing | Retail Brokerage Reporting Unit [Member]
Goodwill [Line Items]
Impairment of goodwill	0	0	$ 0
Goodwill	1,800
Customer Lists
Finite-Lived Intangible Assets [Line Items]
Gross Amount	435	435
Accumulated Amortization	(261)	(241)
Finite-Lived Intangible Assets, Net	$ 174	$ 194
Customer Lists | Weighted Average [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Original Useful Life	20 years	20 years
Weighted Average Remaining Useful Life	10 years	11 years