Derivatives - BS Location (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	$ 296	$ 256
Fair Value of Derivative Instruments, Liabilities	69	43
Derivatives designated as hedging instruments
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	233	190
Fair Value of Derivative Instruments, Liabilities	18	10
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other current assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	148	116
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	61	47
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	14	2
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	3	1
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Current balance sheet location
Location and Fair Value Amount of Derivative Instruments
Derivative Notional Amount	2,815	1,865
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Noncurrent balance sheet location
Location and Fair Value Amount of Derivative Instruments
Derivative Notional Amount	1,240	656
Derivatives designated as hedging instruments \| Commodity price swap contracts \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities		4
Derivatives designated as hedging instruments \| Commodity price swap contracts \| Current balance sheet location
Location and Fair Value Amount of Derivative Instruments
Derivative Notional Amount		20
Derivatives designated as hedging instruments \| Interest rate swap contracts \| Other assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	24	27
Derivatives designated as hedging instruments \| Interest rate swap contracts \| Other liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	1	3
Derivatives designated as hedging instruments \| Interest rate swap contracts \| Noncurrent balance sheet location
Location and Fair Value Amount of Derivative Instruments
Derivative Notional Amount	1,753	1,003
Derivatives not designated as hedging instruments
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	63	66
Fair Value of Derivative Instruments, Liabilities	51	33
Derivatives not designated as hedging instruments \| Foreign currency forward/option contracts \| Other current assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	63	66
Derivatives not designated as hedging instruments \| Foreign currency forward/option contracts \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	51	33
Derivatives not designated as hedging instruments \| Foreign currency forward/option contracts \| Current balance sheet location
Location and Fair Value Amount of Derivative Instruments
Derivative Notional Amount	$ 5,359	$ 6,582

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 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: 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=56946850&loc=SL5624163-113959

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=51825145&loc=SL20226000-175313

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=51814546&loc=SL51823488-111719

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=51814546&loc=SL51823488-111719

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=51824906&loc=SL20225862-175312

Reference 3: 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=56946850&loc=SL5624163-113959

Reference 4: 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=51825145&loc=SL20226000-175313

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