2.2.0.25truefalse41602 - Disclosure - Pension and Other Postretirement Benefits (Benefit Obligations and Plan Assets Associated with Principal Benefit Plans) (Details)truefalseIn Millions, unless otherwise specifiedfalse1falsefalseUSDfalsefalse1/1/2010 - 12/31/2010
USD ($)
USD ($) / shares
$Duration_1_1_2010_To_12_31_2010http://www.sec.gov/CIK0000034088duration2010-01-01T00:00:002010-12-31T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit13Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit15Standardhttp://xbrl.us/us-types/2009-01-31cubicFeetxbrlus0USDUSD$2falsefalseUSDfalsefalse1/1/2009 - 12/31/2009
USD ($)
USD ($) / shares
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{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded and Unfunded Plans [Member]
1/1/2010 - 12/31/2010
USD ($)
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{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded and Unfunded Plans [Member]
1/1/2009 - 12/31/2009
USD ($)
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{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded and Unfunded Plans [Member]
1/1/2010 - 12/31/2010
USD ($)
$Duration_1_1_2010_To_12_31_2010210http://www.sec.gov/CIK0000034088duration2010-01-01T00:00:002010-12-31T00:00:00falsefalsePension Benefits - Non-U.S. [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseBenefit Payments for Funded and Unfunded Plans [Member]xom_DefinedBenefitPlansBenefitPaymentsAxisxbrldihttp://xbrl.org/2006/xbrldixom_BenefitPaymentsForFundedAndUnfundedPlansMemberxom_DefinedBenefitPlansBenefitPaymentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$6falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - Non-U.S. [Member]
{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded and Unfunded Plans [Member]
1/1/2009 - 12/31/2009
USD ($)
$Duration_1_1_2009_To_12_31_200911http://www.sec.gov/CIK0000034088duration2009-01-01T00:00:002009-12-31T00:00:00falsefalsePension Benefits - Non-U.S. [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseBenefit Payments for Funded and Unfunded Plans [Member]xom_DefinedBenefitPlansBenefitPaymentsAxisxbrldihttp://xbrl.org/2006/xbrldixom_BenefitPaymentsForFundedAndUnfundedPlansMemberxom_DefinedBenefitPlansBenefitPaymentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$7falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Postretirement Benefits [Member]
{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded and Unfunded Plans [Member]
1/1/2010 - 12/31/2010
USD ($)
$Duration_1_1_2010_To_12_31_20103222http://www.sec.gov/CIK0000034088duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseOther Postretirement Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPostretirementBenefitPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseBenefit Payments for Funded and Unfunded Plans [Member]xom_DefinedBenefitPlansBenefitPaymentsAxisxbrldihttp://xbrl.org/2006/xbrldixom_BenefitPaymentsForFundedAndUnfundedPlansMemberxom_DefinedBenefitPlansBenefitPaymentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$8falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Postretirement Benefits [Member]
{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded and Unfunded Plans [Member]
1/1/2009 - 12/31/2009
USD ($)
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1/1/2010 - 12/31/2010
USD ($)
$Duration_1_1_2010_To_12_31_20103322http://www.sec.gov/CIK0000034088duration2010-01-01T00:00:002010-12-31T00:00:00falsefalsePension Benefits - U.S. [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$10falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - U.S. [Member]
1/1/2009 - 12/31/2009
USD ($)
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1/1/2008 - 12/31/2008
USD ($)
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1/1/2010 - 12/31/2010
USD ($)
$Duration_1_1_2010_To_12_31_201029http://www.sec.gov/CIK0000034088duration2010-01-01T00:00:002010-12-31T00:00:00falsefalsePension Benefits - Non-U.S. [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$13falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - Non-U.S. [Member]
1/1/2009 - 12/31/2009
USD ($)
$Duration_1_1_2009_To_12_31_200972http://www.sec.gov/CIK0000034088duration2009-01-01T00:00:002009-12-31T00:00:00falsefalsePension Benefits - Non-U.S. [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberUnit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$14falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - Non-U.S. [Member]
1/1/2008 - 12/31/2008
USD ($)
$Duration_1_1_2008_To_12_31_200842http://www.sec.gov/CIK0000034088duration2008-01-01T00:00:002008-12-31T00:00:00falsefalsePension Benefits - Non-U.S. [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberUnit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$15falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Postretirement Benefits [Member]
1/1/2010 - 12/31/2010
USD ($)
$Duration_1_1_2010_To_12_31_2010292http://www.sec.gov/CIK0000034088duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseOther Postretirement Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPostretirementBenefitPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$16falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Postretirement Benefits [Member]
1/1/2009 - 12/31/2009
USD ($)
$Duration_1_1_2009_To_12_31_200973http://www.sec.gov/CIK0000034088duration2009-01-01T00:00:002009-12-31T00:00:00falsefalseOther Postretirement Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPostretirementBenefitPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberUnit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$17falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Postretirement Benefits [Member]
1/1/2008 - 12/31/2008
USD ($)
$Duration_1_1_2008_To_12_31_200843http://www.sec.gov/CIK0000034088duration2008-01-01T00:00:002008-12-31T00:00:00falsefalseOther Postretirement Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPostretirementBenefitPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$2false0us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRateus-gaaptruenainstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsetruefalse00falsefalsefalsefalsefalse2falsetruefalse00falsefalsefalsefalsefalse3falsetruefalse00falsefalsefalsetruefalse4falsetruefalse00falsefalsefalsetruefalse5falsetruefalse00falsefalsefalsetruefalse6falsetruefalse00falsefalsefalsetruefalse7falsetruefalse00falsefalsefalsetruefalse8falsetruefalse00falsefalsefalsetruefalse9truetruefalse0.0550.055falsefalsefalsetruefalse10truetruefalse0.060.06falsefalsefalsetruefalse11falsetruefalse00falsefalsefalsetruefalse12truetruefalse0.0480.048falsefalsefalsetruefalse13truetruefalse0.0520.052falsefalsefalsetruefalse14falsetruefalse00falsefalsefalsetruefalse15truetruefalse0.0550.055falsefalsefalsetruefalse16truetruefalse0.060.06falsefalsefalsetruefalse17falsetruefalse00falsefalsefalsetruefalseOtherus-types:percentItemTypepureThe interest rate used to adjust for the time value of money for the plan.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph j
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
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falsefalse4false0us-gaap_DefinedBenefitPlanBenefitObligationus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsetruefalsefalseperiodstartlabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9truefalsefalse1398100000013981falsetruefalsetruefalse10truefalsefalse1327200000013272falsetruefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12truefalsefalse2334400000023344falsetruefalsetruefalse13truefalsefalse1999000000019990falsetruefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15truefalsefalse67480000006748falsetruefalsetruefalse16truefalsefalse66330000006633falsetruefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetary1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. The projected benefit obligation is measured using assumptions as to future compensation levels if the pension benefit formula is based on those future compensation levels (pay-related, final-pay, final-average-pay, or career-average-pay plans). For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date. Prior to an employee's full eligibility date, the accumulated postretirement benefit obligation as of a particular date for an employee is the portion of the expected postretirement benefit obligation attributed to that employee's service rendered to that date; on and after the full eligibility date, the accumulated and expected postretirement benefit obligations for an employee are the same.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph a
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
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-Number 132R
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-Name Statement of Financial Accounting Standard (FAS)
-Number 106
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-Name Statement of Financial Accounting Standard (FAS)
-Number 87
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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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-Name Statement of Financial Accounting Standard (FAS)
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Name Statement of Financial Accounting Standard (FAS)
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-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph a
falsefalse8false0us-gaap_DefinedBenefitPlanBenefitsPaidus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3truefalsefalse-873000000-873[1],[2]falsefalsefalsetruefalse4truefalsefalse-1665000000-1665[1],[2]falsefalsefalsetruefalse5truefalsefalse-1281000000-1281[1],[2]falsefalsefalsetruefalse6truefalsefalse-1174000000-1174[1],[2]falsefalsefalsetruefalse7truefalsefalse-394000000-394[1],[2]falsefalsefalsetruefalse8truefalsefalse-480000000-480[1],[2]falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12falsefalsefalse00falsefalsefalsetruefalse13falsefalsefalse00falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph a, b
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 106
-Paragraph 518
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 264
Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS106-2
-Paragraph 22
falsefalse9false0us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligationus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12truefalsefalse169000000169falsefalsefalsetruefalse13truefalsefalse16760000001676falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15truefalsefalse2600000026falsefalsefalsetruefalse16truefalsefalse6000000060falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of increase or decrease in the benefit obligation attributed to foreign currency changes. The effects of foreign currency exchange rate changes that are to be disclosed are those applicable to plans of a foreign operation whose functional currency is not the reporting currency.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph a
falsefalse10false0xom_DefinedBenefitPlanAmendmentsAndOtherChangesxomfalsecreditdurationDefined Benefit Plan Amendments And Other Changesfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9truefalsefalse8000000080falsefalsefalsetruefalse10truefalsefalse10000001falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12truefalsefalse163000000163falsefalsefalsetruefalse13truefalsefalse3000000030falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15truefalsefalse178000000178falsefalsefalsetruefalse16truefalsefalse8200000082falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryDefined Benefit Plan Amendments And Other ChangesNo authoritative reference available.falsefalse11false0us-gaap_DefinedBenefitPlanBenefitObligationus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsetruefalseperiodendlabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9truefalsefalse1500700000015007falsefalsefalsetruefalse10truefalsefalse1398100000013981falsefalsefalsetruefalse11truefalsefalse1327200000013272falsefalsefalsetruefalse12truefalsefalse2572200000025722falsefalsefalsetruefalse13truefalsefalse2334400000023344falsefalsefalsetruefalse14truefalsefalse1999000000019990falsefalsefalsetruefalse15truefalsefalse73310000007331falsefalsefalsetruefalse16truefalsefalse67480000006748falsefalsefalsetruefalse17truefalsefalse66330000006633falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetary1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. The projected benefit obligation is measured using assumptions as to future compensation levels if the pension benefit formula is based on those future compensation levels (pay-related, final-pay, final-average-pay, or career-average-pay plans). For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date. Prior to an employee's full eligibility date, the accumulated postretirement benefit obligation as of a particular date for an employee is the portion of the expected postretirement benefit obligation attributed to that employee's service rendered to that date; on and after the full eligibility date, the accumulated and expected postretirement benefit obligations for an employee are the same.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph a
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 6
-Subparagraph a
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph E1
falsefalse12false0us-gaap_DefinedBenefitPlanAccumulatedBenefitObligationus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsetruefalseperiodendlabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9truefalsefalse1276400000012764falsefalsefalsetruefalse10truefalsefalse1161500000011615falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12truefalsefalse2295800000022958falsefalsefalsetruefalse13truefalsefalse2090900000020909falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryFor defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph e
falsefalse13false0us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceivedus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse1500000015falsetruefalsefalsefalse2truefalsefalse2800000028falsetruefalsefalsefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12falsefalsefalse00falsefalsefalsetruefalse13falsefalsefalse00falsefalsefalsetruefalse14falsefalsefalse00falsefalsefalsetruefalse15falsefalsefalse00falsefalsefalsetruefalse16falsefalsefalse00falsefalsefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of the period's gross receipts received from the prescription drug subsidy, which is to be used in the roll forward of the accumulated postretirement benefit obligation of an applicable postretirement benefit plan.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS106-2
-Paragraph 20, 21, 22
falsefalse1Benefit payments for funded plans. 2For 2010 and 2009, other postretirement benefits paid are net of $15 million and $28 million of Medicare subsidy receipts, respectively. 1712Pension and Other Postretirement Benefits (Benefit Obligations and Plan Assets Associated with Principal Benefit Plans) (Details) (USD $)MillionsUnKnownUnKnownUnKnowntruetrue
