Derivative and Hedging Activities - Derivative Instruments in Balance Sheet Table (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability		$ (577)
Derivative Asset, Fair Value, Gross Liability		0
Derivative, Fair Value, Net	$ 81	(577)
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	81
Derivative Liability, Fair Value, Gross Asset	0
Derivative, Fair Value, Net	81
Not Designated as Hedging Instrument [Member] \| Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	81	(504)
Derivative Liability, Fair Value, Gross Asset	0	0
Derivative, Fair Value, Net	81	(504)
Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability		(73)
Derivative Liability, Fair Value, Gross Asset		0
Derivative, Fair Value, Net		(73)
Other Current Assets [Member] \| Not Designated as Hedging Instrument [Member] \| Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	92	1
Derivative Asset, Fair Value, Gross Liability	(21)	(1)
Derivative, Fair Value, Net	71	0
Other Current Liabilities [Member] \| Not Designated as Hedging Instrument [Member] \| Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	(24)	(490)
Derivative Liability, Fair Value, Gross Asset	21	1
Derivative, Fair Value, Net	(3)	(489)
Other Current Liabilities [Member] \| Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability		(73)
Derivative Liability, Fair Value, Gross Asset		0
Derivative, Fair Value, Net		(73)
Other Noncurrent Assets [Member] \| Not Designated as Hedging Instrument [Member] \| Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	14
Derivative Asset, Fair Value, Gross Liability	0
Derivative, Fair Value, Net	14
Other Noncurrent Liabilities [Member] \| Not Designated as Hedging Instrument [Member] \| Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	(1)	(15)
Derivative Liability, Fair Value, Gross Asset	0	0
Derivative, Fair Value, Net	$ (1)	$ (15)

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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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.

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Fair value of asset associated with financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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