v2.4.0.8

Derivative and Financial Instruments - Commodity Balance Sheet (Details) (USD $) In Millions, unless otherwise specified | Jun. 30, 2013 | Dec. 31, 2012
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Prepaid expenses and other current assets [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Commodity derivative assets | $ 1,130 | $ 1,538
Other assets [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Commodity derivative assets | 106 | 105
Other accruals [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Commodity derivative liabilities | 1,166 | 1,509
Other liabilities and deferred credits [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Commodity derivative liabilities | $ 100 | $ 99

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- Definition Fair value as of the balance sheet date of all price risk derivative assets not designated as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 17 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959 + Details
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- Definition Fair value as of the balance sheet date of all price risk derivative liabilities not designated as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 17 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959 + Details
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