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	Jun. 30, 2013	Dec. 31, 2012
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 310	$ 2,298
Derivative Liability, Fair Value, Gross Liability	220	2,468
Notional amount	73,914	236,237
Accrued Interest [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	65	175
Derivative Liability, Fair Value, Gross Liability	8	144
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	172	446
Derivative Liability, Fair Value, Gross Liability	93	63
Notional amount	10,753	18,521
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	138	1,852
Derivative Liability, Fair Value, Gross Liability	127	2,405
Notional amount	63,161	217,716
Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	124	411
Derivative Liability, Fair Value, Gross Liability	83	10
Notional amount	7,716	9,828
Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	137	1,847
Derivative Liability, Fair Value, Gross Liability	116	2,378
Notional amount	61,616	215,252
Fair Value Hedging [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	124	411
Derivative Liability, Fair Value, Gross Liability	83	0
Notional amount	7,018	7,248
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	0	10
Notional amount	698	2,580
Mortgage Servicing Rights And Retained Interests [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	1,616
Derivative Liability, Fair Value, Gross Liability	0	2,299
Notional amount	0	146,405
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	0	49
Derivative Liability, Fair Value, Gross Liability	0	23
Notional amount	4	9,617
Debt Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	48	28
Derivative Liability, Fair Value, Gross Liability	27	29
Notional amount	10,112	17,716
Other Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	89	154
Derivative Liability, Fair Value, Gross Liability	89	27
Notional amount	51,500	41,514
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	48	35
Derivative Liability, Fair Value, Gross Liability	10	53
Notional amount	3,037	8,693
Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	1	5
Derivative Liability, Fair Value, Gross Liability	11	27
Notional amount	1,545	2,464
Eurodollar Future [Member] | Other Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	13	32
Derivative Liability, Fair Value, Gross Liability	13	5
Notional amount	34,700	24,200
Options Held [Member] | Other Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	1
Derivative Liability, Fair Value, Gross Liability	9	8
Notional amount	$ 212	$ 554