Foreign Exchange Risk Management Classification of Outstanding Forward Contracts (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Accounts receivable
Foreign Exchange Risk Management
Forward contracts to purchase and sell foreign currency - Balance sheet location - Accounts receivable	$ 13	$ 29
Other current liabilities
Foreign Exchange Risk Management
Forward contracts to purchase and sell foreign currency - Balance sheet location - Other current liabilities	(23)	(13)
Commitments to purchase foreign currency \| Foreign Exchange Forward
Foreign Exchange Risk Management
Commitments/Options to purchase/sell foreign currency, Notional	67	37
Commitments/Options to purchase/sell foreign currency, Estimated Fair Value	0	(2)
Commitments/Options to sell foreign currency \| Foreign Exchange Forward
Foreign Exchange Risk Management
Commitments/Options to purchase/sell foreign currency, Notional	921	777
Commitments/Options to purchase/sell foreign currency, Estimated Fair Value	(10)	18
Commitments/Options to sell foreign currency \| Foreign Exchange Option
Foreign Exchange Risk Management
Commitments/Options to purchase/sell foreign currency, Notional	3	0
Commitments/Options to purchase/sell foreign currency, Estimated Fair Value	$ 0	$ 0

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

Reference 2: 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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13495-108611

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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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