2.2.0.25falsefalse1730 - Disclosure - Interest Expense Table (Detail)truefalseIn Millionsfalse1falsefalseUSDfalsefalse1/1/2010 - 12/31/2010 USD ($) / shares USD ($) $FROM_Jan01_2010_TO_Dec31_2010http://www.sec.gov/CIK0000773910duration2010-01-01T00:00:002010-12-31T00:00:00usdPerShrDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0MMboeStandardhttp://www.anadarko.com/20101231MMboeapc0USDUSD$2falsefalseUSDfalsefalse1/1/2009 - 12/31/2009 USD ($) USD ($) / shares $FROM_Jan01_2009_TO_Dec31_2009http://www.sec.gov/CIK0000773910duration2009-01-01T00:00:002009-12-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170usdPerShrDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0MMboeStandardhttp://www.anadarko.com/20101231MMboeapc0PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$3falsefalseUSDfalsefalse1/1/2008 - 12/31/2008 USD ($) USD ($) / shares $FROM_Jan01_2008_TO_Dec31_2008http://www.sec.gov/CIK0000773910duration2008-01-01T00:00:002008-12-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0MMboeStandardhttp://www.anadarko.com/20101231MMboeapc0usdPerShrDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$5false0us-gaap_InterestExpenseDebtus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse856000000856falsetruefalsefalsefalse2truefalsefalse734000000734[1]falsetruefalsefalsefalse3truefalsefalse762000000762falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryRepresents the portion of interest incurred in the period on debt arrangements that was charged against earnings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 8 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 34 -Paragraph 21 falsefalseCurrent debt, long-term debt and other6false0apc_InterestExpenseRelatedPartyNotePayableapcfalsedebitdurationInterest expense incurred during the period on note payable to related party.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse2400000024falsefalsefalsefalsefalse2truefalsefalse3900000039falsefalsefalsefalsefalse3truefalsefalse109000000109falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryInterest expense incurred during the period on note payable to related party.No authoritative reference available.falsefalseMidstream subsidiary note payable to a related party7false0apc_LossesGainsOnExtinguishmentOfDebtAndDebtCommitmentTerminationCostsapcfalsedebitdurationLosses Gains on Extinguishment of Debt and Debt Commitment Termination Costsfalsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse103000000103falsefalsefalsefalsefalse2truefalsefalse-2000000-2falsefalsefalsefalsefalse3truefalsefalse-16000000-16falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLosses Gains on Extinguishment of Debt and Debt Commitment Termination CostsNo authoritative reference available.falsefalse(Gain) loss on early debt retirements and commitment termination8false0us-gaap_InterestCostsCapitalizedus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse-128000000-128falsefalsefalsefalsefalse2truefalsefalse-69000000-69falsefalsefalsefalsefalse3truefalsefalse-123000000-123falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of interest that was capitalized during the period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 34 -Paragraph 21 -Subparagraph b falsefalseCapitalized interest9false0us-gaap_InterestExpenseus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse855000000855falsetruefalsefalsefalse2truefalsefalse702000000702falsetruefalsefalsefalse3truefalsefalse732000000732falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe cost of borrowed funds accounted for as interest that was charged against earnings during the period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 34 -Paragraph 21 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 9 -Subsection II Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 9 -Article 9 truefalseInterest expense1Included in 2009 is the reversal of the $78 million liability for unpaid interest related to the DWRRA dispute. See Note 15.35Interest Expense Table (Detail) (USD $)MillionsUnKnownUnKnownUnKnownfalsetrue