Derivative Financial Instruments (Details 4) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Derivative fair values in the consolidated balance sheet for our non-qualifying hedges
Total Derivative Instruments Not Designated As Hedging Instruments Asset At Fair Value		$ (888)
Derivative related liabilities [Member]
Derivative fair values in the consolidated balance sheet for our non-qualifying hedges
Total Derivative Instruments Not Designated As Hedging Instruments Liability At Fair Value	1,173	9
Interest rate swaps [Member] \| Derivative financial assets [Member]
Derivative fair values in the consolidated balance sheet for our non-qualifying hedges
Asset Derivatives Fair Value, non-qualifying hedges		(926)
Interest rate swaps [Member] \| Derivative related liabilities [Member]
Derivative fair values in the consolidated balance sheet for our non-qualifying hedges
Liability Derivatives Fair Value, non-qualifying hedges	1,184	5
Currency swaps and foreign exchange forward contracts [Member] \| Derivative financial assets [Member]
Derivative fair values in the consolidated balance sheet for our non-qualifying hedges
Foreign currency derivative instruments not designated as hedging instruments, asset at fair value		38
Currency swaps and foreign exchange forward contracts [Member] \| Derivative related liabilities [Member]
Derivative fair values in the consolidated balance sheet for our non-qualifying hedges
Foreign currency derivative instruments not designated as hedging instruments, liability at fair value	$ (11)	$ 4

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 10

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

+ References

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- Definition

Fair value as of the balance sheet date of all foreign currency derivative assets not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 17

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

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