Derivative Financial Instruments (Schedule Of The Fair Values Of Derivative Financial Instruments) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value	$ 412
Derivatives Not Designated As Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	7,158	13,893
Derivative Liability, Fair Value	6,741	14,013
Derivatives Not Designated As Hedging Instruments [Member] | Interest-Rate Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	98	1,682
Derivative Liability, Fair Value	121	1,688
Derivatives Not Designated As Hedging Instruments [Member] | Foreign Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	7,060	12,210
Derivative Liability, Fair Value	6,611	12,315
Derivatives Not Designated As Hedging Instruments [Member] | Equity Derivative Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	0	1
Derivative Liability, Fair Value	9	10
Designated As Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	112	126
Derivative Liability, Fair Value	298	330
Designated As Hedging Instruments [Member] | Interest-Rate Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	103	123
Derivative Liability, Fair Value	268	293
Designated As Hedging Instruments [Member] | Foreign Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	9	3
Derivative Liability, Fair Value	$ 30	$ 37