2.2.0.25truefalse41603 - Disclosure - Pension and Other Postretirement Benefits (Change in Plan Assets of Pension and Other Postretirement Benefits) (Details)truefalseIn Millionsfalse1falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - U.S. [Member]
{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded Plans [Member]
1/1/2010 - 12/31/2010
USD ($)
$Duration_1_1_2010_To_12_31_2010422http://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_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseBenefit Payments for Funded Plans [Member]xom_DefinedBenefitPlansBenefitPaymentsAxisxbrldihttp://xbrl.org/2006/xbrldixom_BenefitPaymentsForFundedPlansMemberxom_DefinedBenefitPlansBenefitPaymentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$2falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - U.S. [Member]
{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded Plans [Member]
1/1/2009 - 12/31/2009
USD ($)
$Duration_1_1_2009_To_12_31_20091032http://www.sec.gov/CIK0000034088duration2009-01-01T00:00:002009-12-31T00:00:00falsefalsePension Benefits - U.S. [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseBenefit Payments for Funded Plans [Member]xom_DefinedBenefitPlansBenefitPaymentsAxisxbrldihttp://xbrl.org/2006/xbrldixom_BenefitPaymentsForFundedPlansMemberxom_DefinedBenefitPlansBenefitPaymentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$1false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.exxonmobil.com/taxonomy/role/disclosurepensionandotherpostretirementbenefitschangeinplanassetsofpensionandotherpostretirementbenefitsdetails1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse1falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - U.S. [Member]
{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded Plans [Member]
1/1/2010 - 12/31/2010
USD ($)
$Duration_1_1_2010_To_12_31_2010422http://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_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseBenefit Payments for Funded Plans [Member]xom_DefinedBenefitPlansBenefitPaymentsAxisxbrldihttp://xbrl.org/2006/xbrldixom_BenefitPaymentsForFundedPlansMemberxom_DefinedBenefitPlansBenefitPaymentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$2falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - U.S. [Member]
{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded Plans [Member]
1/1/2009 - 12/31/2009
USD ($)
$Duration_1_1_2009_To_12_31_20091032http://www.sec.gov/CIK0000034088duration2009-01-01T00:00:002009-12-31T00:00:00falsefalsePension Benefits - U.S. [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseBenefit Payments for Funded Plans [Member]xom_DefinedBenefitPlansBenefitPaymentsAxisxbrldihttp://xbrl.org/2006/xbrldixom_BenefitPaymentsForFundedPlansMemberxom_DefinedBenefitPlansBenefitPaymentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse2false0us-gaap_DefinedBenefitPlanBenefitsPaidus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse-677000000-677[1]falsetruefalsefalsefalse2truefalsefalse-1440000000-1440[1]falsetruefalsefalsefalseMonetaryxbrli: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
falsefalse3false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.exxonmobil.com/taxonomy/role/disclosurepensionandotherpostretirementbenefitschangeinplanassetsofpensionandotherpostretirementbenefitsdetails1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - Non-U.S. [Member]
{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded Plans [Member]
1/1/2010 - 12/31/2010
USD ($)
$Duration_1_1_2010_To_12_31_2010211http://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 Plans [Member]xom_DefinedBenefitPlansBenefitPaymentsAxisxbrldihttp://xbrl.org/2006/xbrldixom_BenefitPaymentsForFundedPlansMemberxom_DefinedBenefitPlansBenefitPaymentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - Non-U.S. [Member]
{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded Plans [Member]
1/1/2009 - 12/31/2009
USD ($)
$Duration_1_1_2009_To_12_31_200912http://www.sec.gov/CIK0000034088duration2009-01-01T00:00:002009-12-31T00:00:00falsefalsePension Benefits - Non-U.S. [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseBenefit Payments for Funded Plans [Member]xom_DefinedBenefitPlansBenefitPaymentsAxisxbrldihttp://xbrl.org/2006/xbrldixom_BenefitPaymentsForFundedPlansMemberxom_DefinedBenefitPlansBenefitPaymentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse4false0us-gaap_DefinedBenefitPlanBenefitsPaidus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse-873000000-873[1]falsefalsefalsefalsefalse2truefalsefalse-795000000-795[1]falsefalsefalsefalsefalseMonetaryxbrli: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
falsefalse5false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.exxonmobil.com/taxonomy/role/disclosurepensionandotherpostretirementbenefitschangeinplanassetsofpensionandotherpostretirementbenefitsdetails1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse5falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Postretirement Benefits [Member]
{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded Plans [Member]
1/1/2010 - 12/31/2010
USD ($)
$Duration_1_1_2010_To_12_31_20103323http://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 Plans [Member]xom_DefinedBenefitPlansBenefitPaymentsAxisxbrldihttp://xbrl.org/2006/xbrldixom_BenefitPaymentsForFundedPlansMemberxom_DefinedBenefitPlansBenefitPaymentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$6falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Postretirement Benefits [Member]
{xom_DefinedBenefitPlansBenefitPaymentsAxis} : Benefit Payments for Funded Plans [Member]
1/1/2009 - 12/31/2009
USD ($)
$Duration_1_1_2009_To_12_31_2009102http://www.sec.gov/CIK0000034088duration2009-01-01T00:00:002009-12-31T00:00:00falsefalseOther Postretirement Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPostretirementBenefitPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseBenefit Payments for Funded Plans [Member]xom_DefinedBenefitPlansBenefitPaymentsAxisxbrldihttp://xbrl.org/2006/xbrldixom_BenefitPaymentsForFundedPlansMemberxom_DefinedBenefitPlansBenefitPaymentsAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse6false0us-gaap_DefinedBenefitPlanBenefitsPaidus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse-59000000-59[1]falsefalsefalsefalsefalse2truefalsefalse-57000000-57[1]falsefalsefalsefalsefalseMonetaryxbrli: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
falsefalse7false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.exxonmobil.com/taxonomy/role/disclosurepensionandotherpostretirementbenefitschangeinplanassetsofpensionandotherpostretirementbenefitsdetails1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse7falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - U.S. [Member]
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$8falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - U.S. [Member]
1/1/2009 - 12/31/2009
USD ($)
$Duration_1_1_2009_To_12_31_200982http://www.sec.gov/CIK0000034088duration2009-01-01T00:00:002009-12-31T00:00:00falsefalsePension Benefits - U.S. [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse8false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsetruefalsefalseperiodstartlabel1truefalsefalse1027700000010277falsefalsefalsefalsefalse2truefalsefalse66340000006634falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d(iv)(b)(i)
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 49
falsefalse9false0us-gaap_DefinedBenefitPlanActualReturnOnPlanAssetsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse12350000001235falsefalsefalsefalsefalse2truefalsefalse20130000002013falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d(iv)(b)(i)
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 Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
falsefalse10false0us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssetsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00 falsefalsefalsefalsefalse2falsefalsefalse00 falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of increase or decrease in plan assets 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 b
falsefalse11false0us-gaap_DefinedBenefitPlanContributionsByEmployerus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2truefalsefalse30700000003070falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of contributions made by the employer.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
falsefalse12false0xom_DefinedBenefitOtherIncreaseDecreasexomfalsedebitdurationDefined Benefit Other Increase Decreasefalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00 falsefalsefalsefalsefalse2falsefalsefalse00 falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryDefined Benefit Other Increase DecreaseNo authoritative reference available.falsefalse13false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsetruefalseperiodendlabel1truefalsefalse1083500000010835falsefalsefalsefalsefalse2truefalsefalse1027700000010277falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d(iv)(b)(i)
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 49
falsefalse14false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.exxonmobil.com/taxonomy/role/disclosurepensionandotherpostretirementbenefitschangeinplanassetsofpensionandotherpostretirementbenefitsdetails1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse9falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - Non-U.S. [Member]
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$10falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Benefits - Non-U.S. [Member]
1/1/2009 - 12/31/2009
USD ($)
$Duration_1_1_2009_To_12_31_200972http://www.sec.gov/CIK0000034088duration2009-01-01T00:00:002009-12-31T00:00:00falsefalsePension Benefits - Non-U.S. [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberUnit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse15false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsetruefalsefalseperiodstartlabel1truefalsefalse1540100000015401falsefalsefalsefalsefalse2truefalsefalse1126000000011260falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d(iv)(b)(i)
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 49
falsefalse16false0us-gaap_DefinedBenefitPlanActualReturnOnPlanAssetsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse14820000001482falsefalsefalsefalsefalse2truefalsefalse22010000002201falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d(iv)(b)(i)
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 Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
falsefalse17false0us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssetsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse9900000099falsefalsefalsefalsefalse2truefalsefalse13000000001300falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of increase or decrease in plan assets 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 b
falsefalse18false0us-gaap_DefinedBenefitPlanContributionsByEmployerus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse11840000001184falsefalsefalsefalsefalse2truefalsefalse14560000001456falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of contributions made by the employer.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
falsefalse19false0xom_DefinedBenefitOtherIncreaseDecreasexomfalsedebitdurationDefined Benefit Other Increase Decreasefalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse-528000000-528falsefalsefalsefalsefalse2truefalsefalse-21000000-21falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryDefined Benefit Other Increase DecreaseNo authoritative reference available.falsefalse20false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsetruefalseperiodendlabel1truefalsefalse1676500000016765falsefalsefalsefalsefalse2truefalsefalse1540100000015401falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d(iv)(b)(i)
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 49
falsefalse21false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.exxonmobil.com/taxonomy/role/disclosurepensionandotherpostretirementbenefitschangeinplanassetsofpensionandotherpostretirementbenefitsdetails1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse11falsefalseUSDtruefalse{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$12falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Postretirement Benefits [Member]
1/1/2009 - 12/31/2009
USD ($)
$Duration_1_1_2009_To_12_31_200973http://www.sec.gov/CIK0000034088duration2009-01-01T00:00:002009-12-31T00:00:00falsefalseOther Postretirement Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPostretirementBenefitPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberUnit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse22false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsetruefalsefalseperiodstartlabel1truefalsefalse514000000514falsefalsefalsefalsefalse2truefalsefalse443000000443falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d(iv)(b)(i)
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 49
falsefalse23false0us-gaap_DefinedBenefitPlanActualReturnOnPlanAssetsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse6300000063falsefalsefalsefalsefalse2truefalsefalse9300000093falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d(iv)(b)(i)
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 Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
falsefalse24false0us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssetsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00 falsefalsefalsefalsefalse2falsefalsefalse00 falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of increase or decrease in plan assets 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 b
falsefalse25false0us-gaap_DefinedBenefitPlanContributionsByEmployerus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse3800000038falsefalsefalsefalsefalse2truefalsefalse3600000036falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of contributions made by the employer.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
falsefalse26false0xom_DefinedBenefitOtherIncreaseDecreasexomfalsedebitdurationDefined Benefit Other Increase Decreasefalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse20000002falsefalsefalsefalsefalse2truefalsefalse-1000000-1falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryDefined Benefit Other Increase DecreaseNo authoritative reference available.falsefalse27false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsetruefalseperiodendlabel1truefalsefalse558000000558falsetruefalsefalsefalse2truefalsefalse514000000514falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d(iv)(b)(i)
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 49
falsefalse1Benefit payments for funded plans. 227Pension and Other Postretirement Benefits (Change in Plan Assets of Pension and Other Postretirement Benefits) (Details) (USD $)MillionsUnKnownUnKnownUnKnownfalsetrue