|**Income Taxes (Tables)**                                                                                                      | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
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|**Income Tax Disclosure [Abstract]**                                                                                           |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Components of Income Before Income Taxes Table                                                                                 | Components of income (loss) from continuing operations before income taxes are as follows:Year Ended December 31,201220112010(millions)Domestic$92$(537)$234Foreign1,2641,039614Total$1,356$502$848                                                                                                                                                                                                                                                                                                                                                                                                                                           
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|(millions)                                                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Domestic                                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Foreign                                                                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Total                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Components of Income Tax Provision Table                                                                                       | The income tax provision (benefit) from continuing operations consists of the following:Year Ended December 31,201220112010(millions)Current TaxesFederal$14$11$25State122Foreign14315597Total Current158168124Deferred TaxesFederal60(130)86State1(3)1Foreign172556Total Deferred233(78)93Total Income Tax Provision$391$90$217Effective Tax Rate28.8%17.9%25.6%                                                                                                                                                                                                                                                                             
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|(millions)                                                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Current Taxes                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Federal                                                                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|State                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Foreign                                                                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Total Current                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Deferred Taxes                                                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Federal                                                                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|State                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Foreign                                                                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Total Deferred                                                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Total Income Tax Provision                                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Effective Tax Rate                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Tax Rate Reconciliation Table                                                                                                  | A reconciliation of the federal statutory tax rate to the effective tax rate is as follows:Year Ended December 31,201220112010(percentages)Federal Statutory Rate35.035.035.0Effect ofEarnings of Equity Method Investees(4.9)(13.3)(4.8)State Taxes, Net of Federal Benefit0.2(0.1)0.4Difference Between US and Foreign Rates(4.9)(7.0)(1.2)Foreign Exploration Loss(3.8)(4.2)—Change in Valuation Allowance4.36.6(2.7)Oil Profits Tax - Israel0.92.6(1.9)Tax Contingency1.8——Other, Net0.2(1.7)0.8Effective Rate28.817.925.6                                                                                                                
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|(percentages)                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Federal Statutory Rate                                                                                                         |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Effect of                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Earnings of Equity Method Investees                                                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|State Taxes, Net of Federal Benefit                                                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Difference Between US and Foreign Rates                                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Foreign Exploration Loss                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Change in Valuation Allowance                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Oil Profits Tax - Israel                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Tax Contingency                                                                                                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Other, Net                                                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Effective Rate                                                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Deferred Tax Assets and Liabilities                                                                                            | Deferred tax assets and liabilities resulted from the following:December 31,20122011(millions)Deferred Tax AssetsLoss Carryforwards$235$200Employee Compensation & Benefits134164Foreign Tax Credits3857Other8186Total Deferred Tax Assets488507Valuation Allowance - Foreign Loss Carryforwards(81)(65)Valuation Allowance - Foreign Tax Credits(38)(57)Net Deferred Tax Assets369385Deferred Tax LiabilitiesProperty, Plant and Equipment, Principally Due to Differences in Depreciation, Amortization, Lease Impairment and Abandonments(2,481)(2,409)Total Deferred Tax Liability(2,481)(2,409)Net Deferred Tax Liability$(2,112)$(2,024)
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|(millions)                                                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Deferred Tax Assets                                                                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Loss Carryforwards                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Employee Compensation & Benefits                                                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Foreign Tax Credits                                                                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Other                                                                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Total Deferred Tax Assets                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Valuation Allowance - Foreign Loss Carryforwards                                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Valuation Allowance - Foreign Tax Credits                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Net Deferred Tax Assets                                                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Deferred Tax Liabilities                                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Property, Plant and Equipment, Principally Due to Differences in Depreciation, Amortization, Lease Impairment and Abandonments |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Total Deferred Tax Liability                                                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Net Deferred Tax Liability                                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Deferred Tax Liability Balance Sheet Classifcation                                                                             | Net deferred tax liabilities were classified in the consolidated balance sheets as follows:December 31,20122011(millions)Deferred Income Tax Asset - Current$106$41Deferred Income Tax Liability - Current—(6)Deferred Income Tax Liability - Noncurrent(2,218)(2,059)Net Deferred Tax Liability$(2,112)$(2,024)                                                                                                                                                                                                                                                                                                                              
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|Deferred Income Tax Asset - Current                                                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Deferred Income Tax Liability - Current                                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Deferred Income Tax Liability - Noncurrent                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Net Deferred Tax Liability                                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block]                                                          | A reconciliation of our beginning and ending amounts of unrecognized tax benefits follows:Year Ended December 31, 2012(millions)Unrecognized Tax Benefits, Beginning Balance$—Additions for tax positions related to current year(1)Additions for tax positions of prior years24Reductions for tax positions of prior years—Settlements—Unrecognized Tax Benefits, Ending Balance$23                                                                                                                                                                                                                                                          
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|(millions)                                                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Unrecognized Tax Benefits, Beginning Balance                                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Additions for tax positions related to current year                                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Additions for tax positions of prior years                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Reductions for tax positions of prior years                                                                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Settlements                                                                                                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Unrecognized Tax Benefits, Ending Balance                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               

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