Fair Value Measurement and Fair Value of Financial Instruments (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Trading Liabilities
Reconciliation of assets measured using significant unobservable inputs
Reconciliation of liability balance at fair value on a recurring basis using significant unobservable inputs, beginning of period	$ (266)	$ (187)	$ (264)	$ (136)
Total gains (losses) (realized/unrealized) included in income before taxes	(36)	5	(37)	(43)
Sales	(1)	(1)	(4)	(4)
Settlements	5		7
Reconciliation of liability balance at fair value on a recurring basis using significant unobservable inputs, ending of period	(298)	(183)	(298)	(183)
Changes in unrealized gains (losses) included in income before taxes for liabilities still held at end of period	(36)	5	(37)	(43)
Other Liabilities
Reconciliation of assets measured using significant unobservable inputs
Reconciliation of liability balance at fair value on a recurring basis using significant unobservable inputs, beginning of period	(103)	(96)	(99)	(95)
Total gains (losses) (realized/unrealized) included in income before taxes	(2)	2	(6)	1
Reconciliation of liability balance at fair value on a recurring basis using significant unobservable inputs, ending of period	(105)	(94)	(105)	(94)
Changes in unrealized gains (losses) included in income before taxes for liabilities still held at end of period	$ (2)	$ 2	$ (6)	$ 1