v2.4.0.6

Supplemental Information On Oil And Gas Operations (Capitalized Costs) (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2011 | Dec. 31, 2010
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Capitalized Costs Relating to Oil and Gas Producing Activities, by Geographic Area [Line Items] |  |
Capitalized Costs, Proved properties | $ 61,696 | $ 56,012
United States [Member] |  |
Capitalized Costs Relating to Oil and Gas Producing Activities, by Geographic Area [Line Items] |  |
Capitalized Costs, Proved properties | 41,397 | 36,301
Capitalized Costs, Unproved properties | 2,347 | 2,156
Capitalized Costs, Total oil & gas properties | 43,744 | 38,457
Capitalized Costs, Accumulated DD&A | (29,742) | (28,546)
Net capitalized costs | 14,002 | 9,911
Canada [Member] |  |
Capitalized Costs Relating to Oil and Gas Producing Activities, by Geographic Area [Line Items] |  |
Capitalized Costs, Proved properties | 20,299 | 19,711
Capitalized Costs, Unproved properties | 1,635 | 1,278
Capitalized Costs, Total oil & gas properties | 21,934 | 20,989
Capitalized Costs, Accumulated DD&A | (14,585) | (14,130)
Net capitalized costs | 7,349 | 6,859
North America [Member] |  |
Capitalized Costs Relating to Oil and Gas Producing Activities, by Geographic Area [Line Items] |  |
Capitalized Costs, Proved properties | 61,696 | 56,012
Capitalized Costs, Unproved properties | 3,982 | 3,434
Capitalized Costs, Total oil & gas properties | 65,678 | 59,446
Capitalized Costs, Accumulated DD&A | (44,327) | (42,676)
Net capitalized costs | $ 21,351 | $ 16,770

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- Definition Amount of accumulated depreciation, depletion, amortization and valuation allowance relating to oil and gas producing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59M -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 932 -SubTopic 235 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e61901-109447 + Details
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- Definition The sum of capitalized costs relating to oil and gas producing activities before accounting for accumulated depreciation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59M -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 932 -SubTopic 235 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e61901-109447 + Details
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- Definition Net amount of capitalized costs relating to oil and gas producing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59M -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 932 -SubTopic 235 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e61901-109447 + Details
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- Definition Capitalized costs of proved properties incurred for any combination mineral interests acquisitions; wells and related equipment; support equipment and facilities; and uncompleted wells and equipment and other costs not previously disclosed within this table. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Proved Properties -URI http://asc.fasb.org/extlink&oid=6522428 -Topic 932 -SubTopic 360 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59M -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Properties -URI http://asc.fasb.org/extlink&oid=6808249 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e61901-109447 + Details
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- Definition Capitalized costs of unproved properties incurred for any combination mineral interests acquisitions and other costs not previously disclosed within this table. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Unproved Properties -URI http://asc.fasb.org/extlink&oid=6527831 -Topic 932 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59M -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Properties -URI http://asc.fasb.org/extlink&oid=6808249 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e61901-109447 + Details
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