Derivative Instruments (Details 4) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Interest Rate Contracts [Member] | Other Noninterest Income Expense [Member] | Fair Value Hedges [Member]
Summary of gains (losses) recognized in earnings for fair value hedges, other economic hedges and customer-related positions
Gains (Losses) Recognized in Earnings	$ 3	$ 10	$ 3	$ 24
Futures and Forwards Interest Rate Contract [Member] | Mortgage Banking Revenue [Member] | Other Economic Hedges [Member]
Summary of gains (losses) recognized in earnings for fair value hedges, other economic hedges and customer-related positions
Gains (Losses) Recognized in Earnings	(58)	(10)	111	(24)
Purchased and Written Options Interest Rate Contract [Member] | Mortgage Banking Revenue [Member] | Other Economic Hedges [Member]
Summary of gains (losses) recognized in earnings for fair value hedges, other economic hedges and customer-related positions
Gains (Losses) Recognized in Earnings	245	93	399	142
Receive Fixed Pay Floating Swaps Interest Rate Contract [Member] | Mortgage Banking Revenue [Member] | Other Economic Hedges [Member]
Summary of gains (losses) recognized in earnings for fair value hedges, other economic hedges and customer-related positions
Gains (Losses) Recognized in Earnings	195		138
Receive Fixed Pay Floating Swaps Interest Rate Contract [Member] | Other Noninterest Income Expense [Member]
Summary of gains (losses) recognized in earnings for fair value hedges, other economic hedges and customer-related positions
Gains (Losses) Recognized in Earnings	146	133	6	(14)
Pay Fixed Receive Floating Swaps Interest Rate Contract [Member] | Other Noninterest Income Expense [Member]
Summary of gains (losses) recognized in earnings for fair value hedges, other economic hedges and customer-related positions
Gains (Losses) Recognized in Earnings	(143)	(129)	(4)	11
Foreign exchange cross-currency swaps [Member] | Other Noninterest Income Expense [Member] | Fair Value Hedges [Member]
Summary of gains (losses) recognized in earnings for fair value hedges, other economic hedges and customer-related positions
Gains (Losses) Recognized in Earnings		25	42	98
Forwards Spots and Swaps Foreign Exchange Contract [Member] | Commercial Products Revenue [Member]
Summary of gains (losses) recognized in earnings for fair value hedges, other economic hedges and customer-related positions
Gains (Losses) Recognized in Earnings	12	13	23	27
Equity Contract [Member] | Compensation Expense [Member] | Other Economic Hedges [Member]
Summary of gains (losses) recognized in earnings for fair value hedges, other economic hedges and customer-related positions
Gains (Losses) Recognized in Earnings			(1)	1
Credit Risk Contract [Member] | Other Noninterest Income Expense [Member] | Other Economic Hedges [Member]
Summary of gains (losses) recognized in earnings for fair value hedges, other economic hedges and customer-related positions
Gains (Losses) Recognized in Earnings		(1)	(6)	(2)
Foreign exchange forward contracts [Member] | Commercial Products Revenue [Member] | Other Economic Hedges [Member]
Summary of gains (losses) recognized in earnings for fair value hedges, other economic hedges and customer-related positions
Gains (Losses) Recognized in Earnings	$ (30)	$ (4)	$ (37)	$ (18)