Derivative Instruments - Fair Value of Derivative Contracts (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Derivatives	$ 139	$ 84
Derivative liabilities	32	20
Total fair value of derivative instruments	107	64
Foreign Exchange Contract \| Not Designated as Hedging Instrument \| Other Current Assets
Derivatives, Fair Value [Line Items]
Derivatives	32	20
Foreign Exchange Contract \| Not Designated as Hedging Instrument \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	27	20
Cash Flow Hedging \| Foreign Exchange Contract \| Designated as Hedging Instrument \| Other Current Assets
Derivatives, Fair Value [Line Items]
Derivatives	30	42
Cash Flow Hedging \| Foreign Exchange Contract \| Designated as Hedging Instrument \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	5	0
Fair Value Hedging \| Interest Rate Contract \| Designated as Hedging Instrument \| Other Assets
Derivatives, Fair Value [Line Items]
Derivatives	$ 77	$ 22

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ 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 (a),(c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226000-175313

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