Loans - Net Gains and Losses on Sale (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net Gains Losses On Loan Sales By Portfolio Segment [Line Items]
Total net gains/(losses) on sales of loans (including lower of cost or fair value adjustments)	$ 240	$ 293	$ 228
Consumer, excluding credit card [Member]
Net Gains Losses On Loan Sales By Portfolio Segment [Line Items]
Total net gains/(losses) on sales of loans (including lower of cost or fair value adjustments)	313	122	131
Credit card [Member]
Net Gains Losses On Loan Sales By Portfolio Segment [Line Items]
Total net gains/(losses) on sales of loans (including lower of cost or fair value adjustments)	3	(9)	(24)
Wholesale-related [Member]
Net Gains Losses On Loan Sales By Portfolio Segment [Line Items]
Total net gains/(losses) on sales of loans (including lower of cost or fair value adjustments)	$ (76)	$ 180	$ 121