Derivative Financial Instruments (Effect of Derivative Instruments on the Consolidated Statements of Income) (Details) (USD $) In Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010		Jun. 30, 2011		Jun. 30, 2010
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments				$ 20		$ 240
Interest Rate Contract [Member] | Mortgage Servicing Rights [Member] | Not Designated as Hedging Instrument [Member] | Mortgage Banking Income [Member]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	59	241		20		240
Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member] | Client-Related and Other Risk Management [Member] | Other Income [Member]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	1	(3)		(2)		(4)
Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member] | Mortgage Banking [Member] | Mortgage Banking Income [Member]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	(2)	(27)		(62)		(47)
Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) Recognized in Income, Net	60	213		(40)		192
Not Designated as Hedging Instrument [Member] | Client-Related and Other Risk Management [Member] | Foreign Exchange Contract [Member] | Other Nondeposit Fees and Commissions [Member]
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	2	2		4		3
Interest Rate Contract [Member] | Cash Flow Hedges [Member]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income, Effective Portion, Net	(90)	(137)		(81)		(196)
Derivative Instruments, (Gain) Loss Reclassified from Accumulated OCI into Income, Effective Portion, Net	8	(8)		14		(19)
Interest Rate Contract [Member] | Cash Flow Hedges [Member] | Interest Income [Member]
Derivative Instruments, (Gain) Loss Reclassified from Accumulated OCI into Income, Effective Portion, Net	(6)	(12)		(13)		(28)
Interest Rate Contract [Member] | Cash Flow Hedges [Member] | Interest Expense [Member]
Derivative Instruments, (Gain) Loss Reclassified from Accumulated OCI into Income, Effective Portion, Net	14	4		27		9
Net Investment Hedging [Member] | Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income, Effective Portion, Net	(1)	4		(3)		1
Interest Rate Contract [Member] | Fair Value Hedges [Member]
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments	87	40		126		87
Interest Rate Contract [Member] | Fair Value Hedges [Member] | Interest Income [Member]
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments	(5)	(5)		(10)		(10)
Interest Rate Contract [Member] | Fair Value Hedges [Member] | Interest Expense [Member]
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments	92	45		136		97
Interest Rate Contract [Member] | Fair Value Hedges [Member] | Other Income [Member]
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net		$ (2)	[1]	$ 1	[1]	$ (1)	[1]

[1] All gains and losses recognized in income relate to the ineffective portion of the change in the fair value of the derivative. No portion of the change in fair value of the derivative has been excluded from effectiveness testing.