Derivative Instruments And Hedging Activities (Fair Values Of The Companies' Commodity Derivatives) (Details) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Fair value of derivative assets	$ 176	$ 235
Net derivatives asset	113	106
Fair value of derivative liabilities	297	496
Net derivatives liability	134	191
Derivative Asset [Member]
Impact of netting	(63)	(129)
Derivative Asset [Member] \| Other Current Assets [Member]
Fair value of derivative assets	134	184
Derivative Asset [Member] \| Other Deferred Charges and Non-Current Assets [Member]
Fair value of derivative assets	42	51
Derivative Liability [Member]
Impact of netting	(163)	(305)
Derivative Liability [Member] \| Fair Value of Derivative Liabilities, Current [Member]
Fair value of derivative liabilities	234	385
Derivative Liability [Member] \| Fair Value of Derivative Liabilities, Long Term [Member]
Fair value of derivative liabilities	$ 63	$ 111

Derivative Asset Not Designated As Hedging Instrument Fair Value Net After Offset Under Master Netting Agreement

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- Definition

Derivative Liability Not Designated As Hedging Instrument Fair Value Net After Offset Under Master Netting Agreement

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- Definition

Fair value as of the balance sheet date of the gross assets less the gross liabilities of a derivative asset or group of derivative assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13495-108611

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The amount as of the balance sheet date of the fair value of derivative liabilities that in accordance with the entity's accounting policy were offset against the right to reclaim cash collateral under a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FIN39-1
-Paragraph 10B
-Subparagraph b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Fair value as of the balance sheet date of the gross assets less the gross liabilities of a derivative liability or group of derivative liabilities.

+ References

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