Changes in Accumulated Other Comprehensive (Loss) Income (Details 1) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other non-interest revenue	$ 504	$ 593	$ 1,493	$ 1,679
Interest expense on long-term debt and other	274	329	886	1,026
Total other, net expense	(1,635)	(1,596)	(4,569)	(4,393)
Net Unrealized Investment Gains (Losses) on Investment Securities [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other non-interest revenue	1	21	1	111
Income tax provision for other non-interest revenue	0	(8)	0	(40)
Other non-interest revenue, net of taxes	1	13	1	71
Increase (decrease) due to amounts reclassified into earnings	1	13	1	71
Foreign Currency Translation Adjustments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total other, net expense	0	0	1	(8)
Income tax benefit for other, net expense	0	(1)	0	3
Increase (decrease) due to amounts reclassified into earnings	0	(1)	1	(5)
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	$ 12	$ 2	$ 66