Fair value before effects of master netting arrangements, of a 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.

Reference 1: 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=28370219&loc=SL20226000-175313

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)

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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)

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Fair value before effects of master netting arrangements, of a 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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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ 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)

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-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4D

-Subparagraph (b)

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.13(h))

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open derivatives, commodity, or energy contracts, held at each balance sheet date, that was included in earnings for the period.

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Derivative Instruments and Hedging Activities (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	$ 2		$ 2		$ 17
Derivative Liability, Fair Value	288		288		75
(Gain) Loss on Commodity Derivative Instruments	236	(161)	311	(89)
Cash (Received) Paid in Settlement of Commodity Derivative Instruments	49	(2)	83	(9)
Non-cash Portion of (Gain) Loss on Commodity Derivative Instruments	187	(159)	228	(80)
AOCL amount, net of tax, to be reclassified to interest expense over life of debt			(23)
Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	0		0		1
Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value	199		199		65
Noncurrent Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	2		2		16
Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value	89		89		10
Crude Oil [Member]
Derivatives, Fair Value [Line Items]
(Gain) Loss on Commodity Derivative Instruments	238	(118)	292	(69)
Cash (Received) Paid in Settlement of Commodity Derivative Instruments	46	6	73	14
Non-cash Portion of (Gain) Loss on Commodity Derivative Instruments	192	(124)	219	(83)
Natural Gas [Member]
Derivatives, Fair Value [Line Items]
(Gain) Loss on Commodity Derivative Instruments	(2)	(43)	19	(20)
Cash (Received) Paid in Settlement of Commodity Derivative Instruments	(3)	(8)	10	(23)
Non-cash Portion of (Gain) Loss on Commodity Derivative Instruments	$ (5)	$ (35)	$ 9	$ 3