Derivative Instruments And Hedging Activities (Fair Value Amounts Of Derivative Instruments Reported On Our Condensed Consolidated Balance Sheet) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 4,608	$ 5,701
Derivative Liability, Fair Value, Gross Liability	4,711	5,379
Notional amount	407,254	643,238
Accrued Interest [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	248	459
Derivative Liability, Fair Value, Gross Liability	271	458
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	471	416
Derivative Liability, Fair Value, Gross Liability	132	58
Notional amount	17,327	19,606
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	4,137	5,285
Derivative Liability, Fair Value, Gross Liability	4,579	5,321
Notional amount	389,927	623,632
Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	457	293
Derivative Liability, Fair Value, Gross Liability	13	4
Notional amount	9,798	11,398
Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	4,134	5,148
Derivative Liability, Fair Value, Gross Liability	4,505	5,274
Notional amount	385,546	616,063
Mortgage Servicing Rights And Retained Interests [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	3,801	4,812
Derivative Liability, Fair Value, Gross Liability	4,268	5,012
Notional amount	308,658	523,037
Mortgage Loan Commitments And Mortgage Loans Held-For-Sale [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	150	95
Derivative Liability, Fair Value, Gross Liability	119	107
Notional amount	14,370	24,950
Debt Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	52	81
Derivative Liability, Fair Value, Gross Liability	74	54
Notional amount	23,777	25,934
Other [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	131	160
Derivative Liability, Fair Value, Gross Liability	44	101
Notional amount	38,741	42,142
Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	3	137
Derivative Liability, Fair Value, Gross Liability	74	47
Notional amount	4,381	7,569
Fair Value Hedging [Member] | Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	457	289
Derivative Liability, Fair Value, Gross Liability	0	4
Notional amount	7,218	8,398
Cash Flow Hedging [Member] | Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	4
Derivative Liability, Fair Value, Gross Liability	13	0
Notional amount	2,580	3,000
Net Investment Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	14	123
Derivative Liability, Fair Value, Gross Liability	119	54
Notional amount	$ 7,529	$ 8,208