Derivative Instruments and Hedging Activities (Details 1) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Fair Values of Derivative Instruments Recorded in the Consolidated Balance Sheet
Total Assets	$ 332	$ 306
Derivative Liabilities, Total	154	318
Prepaid Assets and Other [Member]
Fair Values of Derivative Instruments Recorded in the Consolidated Balance Sheet
Current Assets: Derivative instruments	304	167
Deferred Charges and Other [Member]
Fair Values of Derivative Instruments Recorded in the Consolidated Balance Sheet
Other Assets: Deferred charges and other	28	139
Derivative Instruments [Member]
Fair Values of Derivative Instruments Recorded in the Consolidated Balance Sheet
Current Liabilities: Derivative instruments	113	194
Other Liabilities [Member]
Fair Values of Derivative Instruments Recorded in the Consolidated Balance Sheet
Noncurrent Liabilities: Other	$ 41	$ 124

Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

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Fair values as of the balance sheet date for all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments and which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

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Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments which are expected to exist longer than one year or beyond the normal operating cycle, if longer, net of the effects of master netting arrangements.

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Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

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- Definition

Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and which are expected to be extinguished or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

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