2.2.0.25truefalse1510 - Disclosure - Cost of Properties and Equipment by function Table (Detail)truefalseIn Millionsfalse1falsefalseUSDfalsefalse12/31/2010 USD ($) USD ($) / shares $AS_OF_Dec31_2010http://www.sec.gov/CIK0000773910instant2010-12-31T00:00:000001-01-01T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0MMboeStandardhttp://www.anadarko.com/20101231MMboeapc0SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0BcfStandardhttp://www.anadarko.com/20101231Bcfapc0usdPerShrDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2falsefalseUSDfalsefalse12/31/2009 USD ($) USD ($) / shares $AS_OF_Dec31_2009http://www.sec.gov/CIK0000773910instant2009-12-31T00:00:000001-01-01T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0BcfStandardhttp://www.anadarko.com/20101231Bcfapc0PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdPerShrDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0MMboeStandardhttp://www.anadarko.com/20101231MMboeapc0USDUSD$2false0us-gaap_PropertyPlantAndEquipmentGrossus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse5481500000054815falsetruefalsefalsefalse2truefalsefalse5034400000050344falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying amount at the balance sheet date for long-lived physical assets used in the normal conduct of business and not intended for resale. This can include land, physical structures, machinery, vehicles, furniture, computer equipment, construction in progress, and similar items. Amount does not include depreciation.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 falsefalseCost of properties and equipment3false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.anadarko.com/role/disclosurecostofpropertiesandequipmentbyfunctiontabledetail1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalseUSDtruefalse{apc_FunctionsByTypeAxis} : Oil and gas [Member] 12/31/2010 USD ($) $AS_OF_Dec31_2010_apc_FunctionsByTypeAxis_OilAndGasMemberhttp://www.sec.gov/CIK0000773910instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseOil and gas [Member]apc_FunctionsByTypeAxisxbrldihttp://xbrl.org/2006/xbrldiapc_OilAndGasMemberapc_FunctionsByTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4falsefalseUSDtruefalse{apc_FunctionsByTypeAxis} : Oil and gas [Member] 12/31/2009 USD ($) $AS_OF_Dec31_2009_apc_FunctionsByTypeAxis_OilAndGasMemberhttp://www.sec.gov/CIK0000773910instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseOil and gas [Member]apc_FunctionsByTypeAxisxbrldihttp://xbrl.org/2006/xbrldiapc_OilAndGasMemberapc_FunctionsByTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseOil and gas [Member]4false0us-gaap_PropertyPlantAndEquipmentGrossus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse4832800000048328[1]falsefalsefalsefalsefalse2truefalsefalse4432800000044328[1]falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying amount at the balance sheet date for long-lived physical assets used in the normal conduct of business and not intended for resale. This can include land, physical structures, machinery, vehicles, furniture, computer equipment, construction in progress, and similar items. Amount does not include depreciation.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 falsefalseCost of properties and equipment5false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.anadarko.com/role/disclosurecostofpropertiesandequipmentbyfunctiontabledetail1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse5falsefalseUSDtruefalse{apc_FunctionsByTypeAxis} : Gathering, processing and marketing [Member] 12/31/2010 USD ($) $AS_OF_Dec31_2010_apc_FunctionsByTypeAxis_GatheringProcessingAndMarketingMemberhttp://www.sec.gov/CIK0000773910instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseGathering, processing and marketing [Member]apc_FunctionsByTypeAxisxbrldihttp://xbrl.org/2006/xbrldiapc_GatheringProcessingAndMarketingMemberapc_FunctionsByTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$6falsefalseUSDtruefalse{apc_FunctionsByTypeAxis} : Gathering, processing and marketing [Member] 12/31/2009 USD ($) $AS_OF_Dec31_2009_apc_FunctionsByTypeAxis_GatheringProcessingAndMarketingMemberhttp://www.sec.gov/CIK0000773910instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseGathering, processing and marketing [Member]apc_FunctionsByTypeAxisxbrldihttp://xbrl.org/2006/xbrldiapc_GatheringProcessingAndMarketingMemberapc_FunctionsByTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseGathering, processing and marketing [Member]6false0us-gaap_PropertyPlantAndEquipmentGrossus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse40690000004069falsefalsefalsefalsefalse2truefalsefalse37050000003705falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying amount at the balance sheet date for long-lived physical assets used in the normal conduct of business and not intended for resale. This can include land, physical structures, machinery, vehicles, furniture, computer equipment, construction in progress, and similar items. Amount does not include depreciation.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 falsefalseCost of properties and equipment7false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.anadarko.com/role/disclosurecostofpropertiesandequipmentbyfunctiontabledetail1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse7falsefalseUSDtruefalse{apc_FunctionsByTypeAxis} : Minerals [Member] 12/31/2010 USD ($) $AS_OF_Dec31_2010_apc_FunctionsByTypeAxis_MineralsMemberhttp://www.sec.gov/CIK0000773910instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseMinerals [Member]apc_FunctionsByTypeAxisxbrldihttp://xbrl.org/2006/xbrldiapc_MineralsMemberapc_FunctionsByTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$8falsefalseUSDtruefalse{apc_FunctionsByTypeAxis} : Minerals [Member] 12/31/2009 USD ($) $AS_OF_Dec31_2009_apc_FunctionsByTypeAxis_MineralsMemberhttp://www.sec.gov/CIK0000773910instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseMinerals [Member]apc_FunctionsByTypeAxisxbrldihttp://xbrl.org/2006/xbrldiapc_MineralsMemberapc_FunctionsByTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseMinerals [Member]8false0us-gaap_PropertyPlantAndEquipmentGrossus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse11870000001187falsefalsefalsefalsefalse2truefalsefalse11880000001188falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying amount at the balance sheet date for long-lived physical assets used in the normal conduct of business and not intended for resale. This can include land, physical structures, machinery, vehicles, furniture, computer equipment, construction in progress, and similar items. Amount does not include depreciation.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 falsefalseCost of properties and equipment9false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.anadarko.com/role/disclosurecostofpropertiesandequipmentbyfunctiontabledetail1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse9falsefalseUSDtruefalse{apc_FunctionsByTypeAxis} : Other properties and equipment [Member] 12/31/2010 USD ($) $AS_OF_Dec31_2010_apc_FunctionsByTypeAxis_OtherPropertiesAndEquipmentMemberhttp://www.sec.gov/CIK0000773910instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseOther properties and equipment [Member]apc_FunctionsByTypeAxisxbrldihttp://xbrl.org/2006/xbrldiapc_OtherPropertiesAndEquipmentMemberapc_FunctionsByTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$10falsefalseUSDtruefalse{apc_FunctionsByTypeAxis} : Other properties and equipment [Member] 12/31/2009 USD ($) $AS_OF_Dec31_2009_apc_FunctionsByTypeAxis_OtherPropertiesAndEquipmentMemberhttp://www.sec.gov/CIK0000773910instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseOther properties and equipment [Member]apc_FunctionsByTypeAxisxbrldihttp://xbrl.org/2006/xbrldiapc_OtherPropertiesAndEquipmentMemberapc_FunctionsByTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseOther properties and equipment [Member]10false0us-gaap_PropertyPlantAndEquipmentGrossus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse12310000001231falsetruefalsefalsefalse2truefalsefalse11230000001123falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying amount at the balance sheet date for long-lived physical assets used in the normal conduct of business and not intended for resale. This can include land, physical structures, machinery, vehicles, furniture, computer equipment, construction in progress, and similar items. Amount does not include depreciation.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 falsefalseCost of properties and equipment1Includes costs associated with unproved properties of $9.8 billion and $9.5 billion at December 31, 2010 and 2009, respectively.29Cost of Properties and Equipment by function Table (Detail) (USD $)MillionsUnKnownUnKnownUnKnownfalsetrue