2.2.0.25truefalse1930 - Disclosure - Deferred Tax Assets (Liabilities) 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_DeferredTaxAssetsNetCurrentus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse7800000078falsetruefalsefalsefalse2truefalsefalse134000000134falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe current portion of the aggregate tax effects as of the balance sheet date of all future tax deductions arising from temporary differences between tax basis and generally accepted accounting principles basis recognition of assets, liabilities, revenues and expenses, which can only be deducted for tax purposes when permitted under enacted tax laws; after deducting the allocated valuation allowance, if any, to reduce such amount to net realizable value. Deferred tax liabilities and assets shall be classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, shall be classified according to the expected reversal date of the temporary difference. An unrecognized tax benefit that is directly related to a position taken in a tax year that results in a net operating loss carryforward should be presented as a reduction of the related deferred tax asset.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 41, 42, 43 falsefalseNet current deferred tax assets3false0apc_DeferredTaxLiabilitiesOilAndGasExplorationAndDevelopmentOperationsapcfalsecreditinstantThe amount as of the balance sheet date of the estimated future tax effects attributable to the difference between the tax...falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1truefalsefalse-8577000000-8577falsefalsefalsefalsefalse2truefalsefalse-8599000000-8599falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount as of the balance sheet date of the estimated future tax effects attributable to the difference between the tax basis of capital assets and the basis of capital assets computed in accordance with generally accepted accounting principles. The difference in basis, attributable to different capitalization of costs, depreciation, or amortization methodologies, will increase future taxable income when such basis difference is realized. Capital assets include asset that are used in oil and gas exploration and development operations.No authoritative reference available.falsefalseOil and gas exploration and development operations4false0apc_DeferredTaxLiabilitiesMineralOperationsapcfalsecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1truefalsefalse-414000000-414falsefalsefalsefalsefalse2truefalsefalse-411000000-411falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryNo definition available.No authoritative reference available.falsefalseMineral operations5false0apc_DeferredTaxLiabilitiesMidstreamAndOtherDepreciablePropertiesapcfalsecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1truefalsefalse-1314000000-1314falsefalsefalsefalsefalse2truefalsefalse-1286000000-1286falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryNo definition available.No authoritative reference available.falsefalseMidstream and other depreciable properties6false0us-gaap_DeferredTaxLiabilitiesOtherus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1truefalsefalse-1359000000-1359falsefalsefalsefalsefalse2truefalsefalse-853000000-853falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe cumulative amount of the estimated future tax effects attributable to other temporary differences not otherwise specified in this taxonomy that were expensed for tax purposes but capitalized in conformity with generally accepted accounting principles, or which were recognized as revenue under GAAP but not for tax purposes, which will reverse in future periods.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 43 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 11 -Subparagraph a, d, e falsefalseOther7false0apc_DeferredTaxLiabilitiesGrossNoncurrentapcfalsecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegatedtotal1truefalsefalse-11664000000-11664falsefalsefalsefalsefalse2truefalsefalse-11149000000-11149falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryNo definition available.No authoritative reference available.truefalseGross long-term deferred tax liabilities8false0apc_DeferredTaxAssetsOilAndGasExplorationAndDevelopmentCostsapcfalsedebitinstantThe amount as of the balance sheet date of the estimated future tax effects attributable to the difference between the tax...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse253000000253falsefalsefalsefalsefalse2truefalsefalse7900000079falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount as of the balance sheet date of the estimated future tax effects attributable to the difference between the tax basis of oil and gas exploration and development costs and the basis of oil and gas exploration and development costs computed in accordance with generally accepted accounting principles. The difference in basis, attributable to different capitalization of costs, depreciation, or amortization methodologies, will decrease future taxable income when such basis difference is realized.No authoritative reference available.falsefalseOil and gas exploration and development costs9false0us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse311000000311falsefalsefalsefalsefalse2truefalsefalse416000000416falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe sum of the tax effects as of the balance sheet date of the amount of excesses of tax deductions over gross income in a year which cannot be used on the tax returns in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 43, 289 falsefalseNet operating loss carryforward10false0us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsForeignus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse1100000011falsefalsefalsefalsefalse2truefalsefalse7600000076falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe tax effect as of the balance sheet date of the amount of future tax effects arising from unused foreign tax credit carryforwards which will decrease future taxable income if applied in future years; a tax credit carryforward is the amount by which tax credits available for utilization exceeded statutory limits on inclusion in historical filings, and which can only be utilized if sufficient tax-basis income is generated in future periods and providing tax laws continue to allow such utilization.No authoritative reference available.falsefalseForeign tax credit carryforward11false0us-gaap_DeferredTaxAssetsOtherus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse16820000001682falsefalsefalsefalsefalse2truefalsefalse10710000001071falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe tax effect as of the balance sheet date of the amount of estimated future tax deductions arising from other temporary differences not otherwise specified in the taxonomy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 43 falsefalseOther12false0us-gaap_DeferredTaxAssetsGrossNoncurrentus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse22570000002257falsefalsefalsefalsefalse2truefalsefalse16420000001642falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe noncurrent portion of the aggregate tax effects as of the balance sheet date of all future tax deductions arising from temporary differences between tax basis and generally accepted accounting principles basis recognition of assets, liabilities, revenues and expenses, which can only be deducted for tax purposes when permitted under enacted tax laws, before the valuation allowance, if any, to reduce such amount to net realizable value. In a classified statement of financial position, an enterprise shall separate deferred tax liabilities and assets into a current amount and a noncurrent amount. Deferred tax liabilities and assets shall be classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, shall be classified according to the expected reversal date of the temporary difference.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 41, 42, 43, 289 truefalseGross long-term deferred tax assets13false0us-gaap_DeferredTaxAssetsValuationAllowanceNoncurrentus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1truefalsefalse-454000000-454falsefalsefalsefalsefalse2truefalsefalse-418000000-418falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe allocated portion as of the balance sheet date of a valuation allowance pertaining to a deferred tax asset classified as noncurrent for which, based on the weight of available evidence, it is more likely than not, such asset will not be fully realized through future reductions of tax-based income.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 41, 42, 43 falsefalseLess: valuation allowance on deferred tax assets not expected to be realized14false0us-gaap_DeferredTaxAssetsLiabilitiesNetNoncurrentus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse-9861000000-9861falsefalsefalsefalsefalse2truefalsefalse-9925000000-9925falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFor entities that net deferred tax assets and tax liabilities, represents the net amount of deferred tax assets (after reduction for valuation allowance) and liabilities as of the balance sheet date, which result from applying the applicable enacted tax rate to net temporary differences and carryforwards pertaining to assets or liabilities that are classified as noncurrent in the financial statements, or that are expected to reverse after the next twelve months (or beyond the normal operating cycle, if longer). A temporary difference is a difference between the tax basis of an asset or liability and its carrying amount in the financial statements prepared in accordance with generally accepted accounting principles that will reverse in ensuing periods. In a classified statement of financial position, an enterprise shall separate deferred tax liabilities and assets into a current amount and a noncurrent amount. Deferred tax liabilities and assets shall be classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, shall be classified according to the expected reversal date of the temporary difference.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 41, 42, 43 truefalseNet long-term deferred tax liabilities15false0us-gaap_DeferredTaxAssetsLiabilitiesNetus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse-9750000000-9750falsefalsefalsefalsefalse2truefalsefalse-9778000000-9778falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFor entities that net deferred tax assets and tax liabilities, represents the unclassified net amount of deferred tax assets and liabilities as of the balance sheet date, which result from applying the applicable enacted tax rate to net temporary differences and carryforwards pertaining to assets or liabilities. A temporary difference is a difference between the tax basis of an asset or liability and its carrying amount in the financial statements prepared in accordance with generally accepted accounting principles that will reverse in ensuing periods.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 42, 43 truefalseTotal deferred taxes16false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.anadarko.com/role/disclosuredeferredtaxassetsliabilitiestabledetail1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalseUSDtruefalse{apc_NetLongTermDeferredTaxAssetsByTypeAxis} : Portion that is unable to net against gross long-term deferred tax liabilities [Member] 12/31/2010 USD ($) $AS_OF_Dec31_2010_apc_NetLongTermDeferredTaxAssetsByTypeAxis_PortionThatIsUnableToNetAgainstGrossLongTermDeferredTaxLiabilitiesMemberhttp://www.sec.gov/CIK0000773910instant2010-12-31T00:00:000001-01-01T00:00:00falsefalsePortion that is unable to net against gross long-term deferred tax liabilities [Member]apc_NetLongTermDeferredTaxAssetsByTypeAxisxbrldihttp://xbrl.org/2006/xbrldiapc_PortionThatIsUnableToNetAgainstGrossLongTermDeferredTaxLiabilitiesMemberapc_NetLongTermDeferredTaxAssetsByTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4falsefalseUSDtruefalse{apc_NetLongTermDeferredTaxAssetsByTypeAxis} : Portion that is unable to net against gross long-term deferred tax liabilities [Member] 12/31/2009 USD ($) $AS_OF_Dec31_2009_apc_NetLongTermDeferredTaxAssetsByTypeAxis_PortionThatIsUnableToNetAgainstGrossLongTermDeferredTaxLiabilitiesMemberhttp://www.sec.gov/CIK0000773910instant2009-12-31T00:00:000001-01-01T00:00:00falsefalsePortion that is unable to net against gross long-term deferred tax liabilities [Member]apc_NetLongTermDeferredTaxAssetsByTypeAxisxbrldihttp://xbrl.org/2006/xbrldiapc_PortionThatIsUnableToNetAgainstGrossLongTermDeferredTaxLiabilitiesMemberapc_NetLongTermDeferredTaxAssetsByTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalsePortion that is unable to net against gross long-term deferred tax liabilities [Member]17false0us-gaap_DeferredTaxAssetsNetNoncurrentus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse3300000033falsefalsefalsefalsefalse2truefalsefalse1300000013falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe noncurrent portion as of the balance sheet date of the aggregate carrying amount of all future tax deductions arising from temporary differences between tax basis and generally accepted accounting principles basis recognition of assets, liabilities, revenues and expenses, which can only be deducted for tax purposes when permitted under enacted tax laws; after the valuation allowance, if any, to reduce such amount to net realizable value. Deferred tax liabilities and assets shall be classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, shall be classified according to the expected reversal date of the temporary difference.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 41, 42, 43 falsefalseNet long-term deferred tax assets18false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.anadarko.com/role/disclosuredeferredtaxassetsliabilitiestabledetail1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse5falsefalseUSDtruefalse{apc_NetLongTermDeferredTaxAssetsByTypeAxis} : Portion that is able to net against gross long-term deferred tax liabilities [Member] 12/31/2010 USD ($) $AS_OF_Dec31_2010_apc_NetLongTermDeferredTaxAssetsByTypeAxis_PortionThatIsAbleToNetAgainstGrossLongTermDeferredTaxLiabilitiesMemberhttp://www.sec.gov/CIK0000773910instant2010-12-31T00:00:000001-01-01T00:00:00falsefalsePortion that is able to net against gross long-term deferred tax liabilities [Member]apc_NetLongTermDeferredTaxAssetsByTypeAxisxbrldihttp://xbrl.org/2006/xbrldiapc_PortionThatIsAbleToNetAgainstGrossLongTermDeferredTaxLiabilitiesMemberapc_NetLongTermDeferredTaxAssetsByTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$6falsefalseUSDtruefalse{apc_NetLongTermDeferredTaxAssetsByTypeAxis} : Portion that is able to net against gross long-term deferred tax liabilities [Member] 12/31/2009 USD ($) $AS_OF_Dec31_2009_apc_NetLongTermDeferredTaxAssetsByTypeAxis_PortionThatIsAbleToNetAgainstGrossLongTermDeferredTaxLiabilitiesMemberhttp://www.sec.gov/CIK0000773910instant2009-12-31T00:00:000001-01-01T00:00:00falsefalsePortion that is able to net against gross long-term deferred tax liabilities [Member]apc_NetLongTermDeferredTaxAssetsByTypeAxisxbrldihttp://xbrl.org/2006/xbrldiapc_PortionThatIsAbleToNetAgainstGrossLongTermDeferredTaxLiabilitiesMemberapc_NetLongTermDeferredTaxAssetsByTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalsePortion that is able to net against gross long-term deferred tax liabilities [Member]19false0us-gaap_DeferredTaxAssetsNetNoncurrentus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse18030000001803falsetruefalsefalsefalse2truefalsefalse12240000001224falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe noncurrent portion as of the balance sheet date of the aggregate carrying amount of all future tax deductions arising from temporary differences between tax basis and generally accepted accounting principles basis recognition of assets, liabilities, revenues and expenses, which can only be deducted for tax purposes when permitted under enacted tax laws; after the valuation allowance, if any, to reduce such amount to net realizable value. Deferred tax liabilities and assets shall be classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, shall be classified according to the expected reversal date of the temporary difference.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 41, 42, 43 falsefalseNet long-term deferred tax assets218Deferred Tax Assets (Liabilities) Table (Detail) (USD $)MillionsUnKnownUnKnownUnKnownfalsetrue