2.2.0.25truefalse41701 - Disclosure - Disclosures about Segments and Related Information (Narrative) (Details)truefalseIn Millionsfalse1falsefalseUSDfalsefalse1/1/2010 - 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/2009-01-31cubicFeetxbrlus0Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2falsefalseUSDfalsefalse1/1/2009 - 12/31/2009
USD ($)
USD ($) / shares
$Duration_1_1_2009_To_12_31_2009http://www.sec.gov/CIK0000034088duration2009-01-01T00:00:002009-12-31T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit13Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$3falsefalseUSDfalsefalse1/1/2008 - 12/31/2008
USD ($)
USD ($) / shares
$Duration_1_1_2008_To_12_31_2008http://www.sec.gov/CIK0000034088duration2008-01-01T00:00:002008-12-31T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit13Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit14Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$2false0xom_InterestRelatedValdezPunitiveDamagesNetOfTaxxomfalsedebitinstantInterest Related Valdez Punitive Damages Net Of Taxfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2truefalsefalse140000000140falsetruefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryInterest Related Valdez Punitive Damages Net Of TaxNo authoritative reference available.falsefalse3false0us-gaap_InterestExpenseOtherus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse4100000041falsefalsefalsefalsefalse2truefalsefalse500000000500falsefalsefalsefalsefalse3truefalsefalse498000000498falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryInterest expense on all other items not previously classified. For example, includes dividends associated with redeemable preferred stock of a subsidiary that is treated as a liability in the parent's consolidated balance sheet.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 01-6
-Paragraph 14
-Subparagraph l
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher OTS
-Name Federal Regulation (FR)
-Number Title 12
-Chapter V
-Section 563c.102
-Paragraph 6
-Subsection II
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Audit and Accounting Guide (AAG)
-Number AAG-BRD
-Chapter 4
-Paragraph 55
-IssueDate 2006-05-01
falsefalse4false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.exxonmobil.com/taxonomy/role/disclosuredisclosuresaboutsegmentsandrelatedinformationnarrativedetails1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse4falsefalseUSDtruefalse{us-gaap_SegmentReportingInformationBySegmentAxis} : Upstream Non-U.S. [Member]
1/1/2008 - 12/31/2008
USD ($)
$Duration_1_1_2008_To_12_31_200835http://www.sec.gov/CIK0000034088duration2008-01-01T00:00:002008-12-31T00:00:00falsefalseUpstream Non-U.S. [Member]us-gaap_SegmentReportingInformationBySegmentAxisxbrldihttp://xbrl.org/2006/xbrldixom_UpstreamNonUsMemberus-gaap_SegmentReportingInformationBySegmentAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse5false0xom_GainLossOnDisposalOfAssetsNetOfTaxxomfalsecreditdurationGain Loss On Disposal Of Assets Net Of Taxfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3truefalsefalse16200000001620falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryGain Loss On Disposal Of Assets Net Of TaxNo authoritative reference available.falsefalse6false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.exxonmobil.com/taxonomy/role/disclosuredisclosuresaboutsegmentsandrelatedinformationnarrativedetails1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse5falsefalseUSDtruefalse{us-gaap_SegmentReportingInformationBySegmentAxis} : Corporate and Financing [Member]
1/1/2008 - 12/31/2008
USD ($)
$Duration_1_1_2008_To_12_31_200831http://www.sec.gov/CIK0000034088duration2008-01-01T00:00:002008-12-31T00:00:00falsefalseCorporate and Financing [Member]us-gaap_SegmentReportingInformationBySegmentAxisxbrldihttp://xbrl.org/2006/xbrldixom_CorporateAndFinancingMemberus-gaap_SegmentReportingInformationBySegmentAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse7false0xom_ValdezPunitiveDamagesNetOfTaxxomfalsedebitdurationValdez Punitive Damages Net Of Taxfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3truefalsefalse460000000460falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryValdez Punitive Damages Net Of TaxNo authoritative reference available.falsefalse36Disclosures about Segments and Related Information (Narrative) (Details) (USD $)MillionsUnKnownUnKnownUnKnownfalsetrue
