2.2.0.25truefalse1058 - Disclosure - Effects of One Percent Change in Assumed Health Care Cost Trend (Detail)truefalseIn Millionsfalse1falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : U.S. Postretirement Medical Benefits
1/1/2010 - 12/31/2010
USD ($)
$eol_PE10216---1010-K0013_STD_365_20101231_0_402249x412477http://www.sec.gov/CIK0001090727duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseU.S. Postretirement Medical Benefitsus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_UnitedStatesPostretirementBenefitPlansOfUSEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170pureStandardhttp://www.xbrl.org/2003/instancepure0USDUSD$2true0us-gaap_DefinedBenefitPlanDisclosureLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalse<
hasScenarios>falseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalse3false0us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponentsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse90000009falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs. (For purposes of this disclosure, all other assumptions shall be held constant, and the effects shall be measured based on the substantive plan that is the basis for the accounting.)Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph m
falsefalse4false0us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligationus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse<
Cell>1truefalsefalse7400000074falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits. (For purposes of this disclosure, all other assumptions shall be held constant, and the effects shall be measured based on the substantive plan that is the basi
s for the accounting.)Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph m
falsefalse5false0us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponentsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1truefalsefalse-9000000-9falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe effect of a one-percentage- point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs. (For purposes of this disclosure, all other assumptions shall be held constant, and the effects shall be measur
ed based on the substantive plan that is the basis for the accounting.)Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph m
falsefalse6false0us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligationus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1truefalsefalse-78000000-78falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits. (For purposes of this disclosure, all other assumptions shall be held constant, and the effects shall be measured based on the substan
tive plan that is the basis for the accounting.)Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph m
falsefalse15Effects of One Percent Change in Assumed Health Care Cost Trend (Detail) (U.S. Postretirement Medical Benefits, USD $)MillionsUnKnownUnKnownUnKnownfalsetrue
