Derivative Instruments and Hedging Activities (Pre-Tax Gains (Losses) On Derivatives Designated As Hedging Instruments) (Details) - Designated As Hedging Instrument [Member] - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Derivative Instruments, Gains (Loss) [Line Items]
Total amount recognized in earnings	$ (19)	$ (51)	$ (13)	$ (97)
Other Income (Expense) [Member]
Derivative Instruments, Gains (Loss) [Line Items]
FX Contracts effective amount recognized in earnings	0	(3)	(2)	(25)
Interest Expense [Member]
Derivative Instruments, Gains (Loss) [Line Items]
Interest contracts effective amount recognized in earnings	0	(2)	0	(2)
Cost Of Products Sold [Member]
Derivative Instruments, Gains (Loss) [Line Items]
Commodity Contracts effective amount recognized in earnings	(15)	(37)	(20)	(61)
Commodity contracts ineffective amount recognized in earnings	(4)	1	5	5
Revenues [Member]
Derivative Instruments, Gains (Loss) [Line Items]
Commodity Contracts effective amount recognized in earnings	0	(9)	0	(14)
Commodity contracts ineffective amount recognized in earnings	$ 0	$ (1)	$ 4	$ 0

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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The amount of net gains or losses on foreign currency cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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The net gain (loss) recognized in earnings during the period due to ineffectiveness in price risk cash flow hedges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

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