2.2.0.25truefalse41403 - Disclosure - Incentive Program (Summary of Grant Value of Restricted Stock and Units) (Details)truefalseIn Millions, except Per Share datafalse1falsefalseUSDtruefalse{us-gaap_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardAwardTypeAndPlanNameAxis} : Acquisition of XTO Energy Inc [Member]
{us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis} : Restricted Stock [Member]
1/1/2010 - 12/31/2010
USD ($)
USD ($) / shares
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{us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis} : Restricted Stock [Member]
1/1/2009 - 12/31/2009
USD ($)
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{us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis} : Restricted Stock [Member]
1/1/2008 - 12/31/2008
USD ($)
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(c)
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph c(1)
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 10, 15
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{us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis} : Restricted Stock [Member]
1/1/2010 - 12/31/2010
USD ($)
USD ($) / shares
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{us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis} : Restricted Stock [Member]
1/1/2009 - 12/31/2009
USD ($)
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{us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis} : Restricted Stock [Member]
1/1/2008 - 12/31/2008
USD ($)
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