Derivatives And Hedging Activities Effect of Derivative Instruments in Consolidated Statement of Operations (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	$ 22	$ (8)	$ (4)	$ 41
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	1			18
Derivative Instruments, Gain Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing	0	0	0	0
Derivative Instruments, Gain Reclassified from Accumulated OCI into Income, Effective Portion		6	5
Designated as Hedging Instrument \| Cash Flow Hedging \| Commodity derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	(14)	15	(33)	26
Derivative Instruments, Gain Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing	0	0	0	0
Derivative Instruments, Gain Reclassified from Accumulated OCI into Income, Effective Portion	1	5	16	8
Designated as Hedging Instrument \| Cash Flow Hedging \| Foreign currency derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	33	(13)	30	41
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	2		11	26
Derivative Instruments, Gain Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing	0	0	0	0
Derivative Instruments, Gain Reclassified from Accumulated OCI into Income, Effective Portion		1
Designated as Hedging Instrument \| Net Investment Hedging \| Foreign currency derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	3	(10)	(1)	(26)
Derivative Instruments, Gain Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing	0	0	0	0
Derivative Instruments, Gain Reclassified from Accumulated OCI into Income, Effective Portion	0	0	0	0
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Loss on Derivative				(5)
Derivative, Loss on Derivative	0	0	2
Not Designated as Hedging Instrument \| Foreign currency derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Loss on Derivative				$ (5)
Derivative, Loss on Derivative	$ 0	$ 0	$ 2

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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The effective portion of gain reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The portion of gains on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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