Changes in Accumulated Other Comprehensive (Loss) Income (Details 1) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other non-interest revenue	$ 521	$ 585	$ 989	$ 1,086
Interest expense on long-term debt and other	305	352	612	697
Total other, net expense	(1,535)	(1,248)	(2,934)	(2,797)
Net Unrealized Investment Gains (Losses) on Investment Securities [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other non-interest revenue	0	45	0	90
Income tax provision for other non-interest revenue	0	(16)	0	(32)
Other non-interest revenue, net of taxes	0	29	0	58
Increase (decrease) due to amounts reclassified into earnings	0	29	0	58
Foreign Currency Translation Adjustments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total other, net expense	1	(6)	1	(8)
Income tax benefit for other, net expense	0	3	0	4
Increase (decrease) due to amounts reclassified into earnings	1	3	1	4
Accumulated Other Comprehensive (Loss) Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Increase (decrease) due to amounts reclassified into earnings	$ 1	$ 26	$ 1	$ 54