Derivative Instruments - Fair Value of Derivative Contracts (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative assets	$ 90	$ 154
Derivative liabilities	59	48
Total fair value of derivative instruments	31	106
Foreign Exchange Contract \| Designated as Hedging Instrument \| Other Current Assets \| Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative assets	9	67
Foreign Exchange Contract \| Designated as Hedging Instrument \| Other Current Liabilities \| Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative liabilities	20	3
Foreign Exchange Contract \| Not Designated as Hedging Instrument \| Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative assets	57	64
Foreign Exchange Contract \| Not Designated as Hedging Instrument \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	39	45
Interest Rate Contract \| Designated as Hedging Instrument \| Other Assets \| Fair Value Hedging
Derivatives, Fair Value [Line Items]
Derivative assets	$ 24	$ 23

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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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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