Financial Instruments (Fair Value of Derivative Instruments) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives designated as hedging instruments, Asset Derivatives	$ 34	$ 3
Derivatives not designated as hedging instruments, Asset Derivatives	97	139
Derivatives designated as hedging instruments, Liability Derivatives	380	248
Derivatives not designated as hedging instruments, Liability Derivatives	$ 230	$ 71

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Fair value as of the balance sheet date of all foreign currency derivative assets designated as cash flow hedging instruments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624163-113959

+ Details

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- Definition

Fair value as of the balance sheet date of all foreign currency derivative liabilities designated as cash flow hedging instruments.

+ References

+ Details

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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 Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624163-113959

+ Details

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- Definition

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

+ References

Reference 1: 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=56946850&loc=SL5624163-113959

+ Details

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