Derivative Financial Instruments (Effect of Derivative Instruments on the Consolidated Statements of Income) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Gain (loss) on interest rate derivative instruments not designated as hedging instruments	$ (197)	$ 128	$ 394
Cash Flow Hedges [Member] | Interest Rate Contract [Member]
Derivative instruments, gain (loss) recognized in OCI, effective portion, net	204	(84)	(225)
Derivative instruments, (gain) loss reclassified from AOCI into income, effective portion, net	(77)	(61)	(46)
Cash Flow Hedges [Member] | Interest Rate Contract [Member] | Interest Income [Member]
Derivative instruments, (gain) loss reclassified from AOCI into income, effective portion, net	0	11	26
Cash Flow Hedges [Member] | Interest Rate Contract [Member] | Interest Expense [Member]
Derivative instruments, (gain) loss reclassified from AOCI into income, effective portion, net	(77)	(72)	(72)
Fair Value Hedges [Member] | Interest Rate Contract [Member]
Derivative instruments, gain (loss) recognized in income, net	120	267	293
Fair Value Hedges [Member] | Interest Rate Contract [Member] | Interest Income [Member]
Derivative instruments, gain (loss) recognized in income, net	(21)	(21)	(21)
Fair Value Hedges [Member] | Interest Rate Contract [Member] | Interest Expense [Member]
Derivative instruments, gain (loss) recognized in income, net	141	288	314
Not Designated as Hedging Instrument [Member]
Gain (loss) on interest rate derivative instruments not designated as hedging instruments	(187)	231	340
Not Designated as Hedging Instrument [Member] | Client-Related and Other Risk Management [Member] | Interest Rate Contract [Member] | Other Income [Member]
Gain (loss) on interest rate derivative instruments not designated as hedging instruments	26	35	10
Not Designated as Hedging Instrument [Member] | Client-Related and Other Risk Management [Member] | Foreign Exchange Contract [Member] | Other Income [Member]
Gain (loss) on interest rate derivative instruments not designated as hedging instruments	11	9	6
Not Designated as Hedging Instrument [Member] | Mortgage Banking [Member] | Interest Rate Contract [Member] | Mortgage Banking Income [Member]
Gain (loss) on interest rate derivative instruments not designated as hedging instruments	(27)	59	(70)
Not Designated as Hedging Instrument [Member] | Residential MSR [Member] | Interest Rate Contract [Member] | Mortgage Banking Income [Member]
Gain (loss) on interest rate derivative instruments not designated as hedging instruments	$ (197)	$ 128	$ 394