Derivative and Financial Instruments - FX Balance Sheet (Details 3) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Foreign currency exchange derivative assets	$ 0	$ 1
Other Accruals [Member]
Derivatives, Fair Value [Line Items]
Foreign currency exchange derivative liabilities	$ 2	$ 168

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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=64837297&loc=SL5624163-113959

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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

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