v2.4.0.6

Supplemental Information On Oil And Gas Operations (Standardized Measure Of Discounted Future Net Cash Flows Related To Interest In Proved Reserves) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
United States [Member] |  |  |
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items] |  |  |
Future cash flows | $ 69,305 | $ 58,093 | $ 44,571
Future costs development | (6,817) | (6,220) | (6,814)
Future costs production | (26,217) | (24,223) | (22,184)
Future income tax expense | (11,432) | (8,643) | (3,572)
Future net cash flows | 24,839 | 19,007 | 12,001
10% discount to reflect timing of cash flows | (13,492) | (10,164) | (6,121)
Standardized measure of discounted future net cash flows | 11,347 | 8,843 | 5,880
Canada [Member] |  |  |
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items] |  |  |
Future cash flows | 36,786 | 35,948 | 28,442
Future costs development | (4,678) | (4,526) | (4,132)
Future costs production | (15,063) | (12,249) | (9,847)
Future income tax expense | (3,763) | (4,209) | (3,408)
Future net cash flows | 13,282 | 14,964 | 11,055
10% discount to reflect timing of cash flows | (6,785) | (7,455) | (5,532)
Standardized measure of discounted future net cash flows | 6,497 | 7,509 | 5,523
North America [Member] |  |  |
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items] |  |  |
Future cash flows | 106,091 | 94,041 | 73,013
Future costs development | (11,495) | (10,746) | (10,946)
Future costs production | (41,280) | (36,472) | (32,031)
Future income tax expense | (15,195) | (12,852) | (6,980)
Future net cash flows | 38,121 | 33,971 | 23,056
10% discount to reflect timing of cash flows | (20,277) | (17,619) | (11,653)
Standardized measure of discounted future net cash flows | $ 17,844 | $ 16,352 | $ 11,403

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- Definition This is the amount that is derived from using a discount rate of ten percent a year to reflect the timing of the future net cash flows relating to proved oil and gas reserves. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59Y -Subparagraph e -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 30 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62424-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 31 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62455-109447 + Details
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- Definition Cash proceeds expected from future sale of oil and gas from proved reserves located in this geographic region. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59Y -Subparagraph a -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 30 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62424-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 31 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62455-109447 + Details
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- Definition The future cost of developing oil and gas from proved reserves located in this geographic region. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59Y -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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 30 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62424-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 31 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62455-109447 + Details
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- Definition The estimated future income tax expenses that will be incurred based on the future income less future expenses derived from production and sale of proved oil and gas reserves in this geographic region. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59Y -Subparagraph c -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 30 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62424-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 31 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62455-109447 + Details
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- Definition These amounts are the result of subtracting future development and production costs and future income tax expenses from future cash inflows for each geographic region where proved oil and gas reserves exist. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59Y -Subparagraph d -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 30 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62424-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 31 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62455-109447 + Details
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- Definition The future cost of producing oil and gas from proved reserves located in this geographic region. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59Y -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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 30 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62424-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 31 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62455-109447 + Details
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- Definition This amount is the future net cash flows less the computed discount. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59Y -Subparagraph f -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 30 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62424-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 31 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e62455-109447 + Details
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