Expected percentage point change in future period consolidated effective tax rate due to changes in Israeli Oil Profits Taxation Law.

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Expected percentage point change in future period consolidated effective tax rate due to changes in the UK Oil Profits Taxation Law.

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The earliest tax year being audited in connection with the income tax examination.

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Increase in deferred tax liability due to change in foreign tax law change.

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Increase in deferred tax expense due to change in tax law change.

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Expected effective tax rate on UK oil and gas income following enactment of oil and gas tax increases

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Effective tax rate on UK oil and gas income prior to enactment of oil and gas tax increases.

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Supplementary charge levied on oil and gas production in the UK after change in tax law in March 2011

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Supplementary charge levied on oil and gas production in the UK before change in tax law in March 2011.

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The component of income tax expense for the period representing amounts of income taxes paid or payable (or refundable) for the period for all income tax obligations as determined by applying the provisions of relevant enacted tax laws to relevant amounts of taxable income (loss) from continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section I

-Subsection 7

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 289

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-Name Regulation S-X (SX)

-Number 210

-Section 08

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-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 45

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The component of income tax expense for the period representing the net change in the entity's deferred tax assets and liabilities pertaining to continuing operations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

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-Section I

-Subsection 7

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-Name Statement of Financial Accounting Standard (FAS)

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-Name Statement of Financial Accounting Standard (FAS)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

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A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

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-Subparagraph 2

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The sum of the current income tax expense (benefit) and the deferred income tax expense (benefit) pertaining to continuing operations.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 45

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The amount of the change in the period in the valuation allowance for a specified deferred tax asset.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 43

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 26

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Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Notes to Financial Statements [Abstract]
Current	$ 179	$ 42	$ 289	$ 180
Deferred	102	24	147	109
Total Income Tax Provision	281	66	436	289
Effective Tax Rate	39.00%	22.00%	37.00%	30.00%
Change in the valuation allowance			16	(28)
Expected percentage point change in future period consolidated effective tax rate due to changes in Israeli Oil Profits Taxation Law (in hundredths)			2.00%
UK supplementary charge levied on oil and gas income prior to March 2011 increase (in hundredths)			20.00%
UK supplementary charge levied on oil and gas income following March 2011 increase (in hundredths)			32.00%
UK oil and gas income expected tax rate prior to March 2011 (in hundredths)			50.00%
UK oil and gas income expected tax rate after March 2011 (in hundredths)			62.00%
Expected increase in consolidated effective income tax rate due to changes in tax laws in the UK (in hundredths)			4.00%
Years Remaining Open to Examination [Abstract]
Increase in UK deferred tax liability due to change in UK tax law	34
Increase in UK income tax expense due to change in UK tax law	$ 34
US [Member]
Years Remaining Open to Examination [Abstract]
Earliest years remaining open to examinations			2006
Equatorial Guinea [Member]
Years Remaining Open to Examination [Abstract]
Earliest years remaining open to examinations			2007
Israel [Member]
Years Remaining Open to Examination [Abstract]
Earliest years remaining open to examinations			2008
UK [Member]
Years Remaining Open to Examination [Abstract]
Earliest years remaining open to examinations			2007
Netherlands [Member]
Years Remaining Open to Examination [Abstract]
Earliest years remaining open to examinations			2009
China [Member]
Years Remaining Open to Examination [Abstract]
Earliest years remaining open to examinations			2006