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12/31/2009
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12/31/2010
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12/31/2009
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12/31/2009
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12/31/2010
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12/31/2009
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12/31/2010
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12/31/2009
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12/31/2010
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12/31/2009
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12/31/2010
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12/31/2009
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12/31/2009
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12/31/2009
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12/31/2009
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12/31/2009
USD ($)
$As_Of_12_31_200928http://www.sec.gov/CIK0000034088instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseOther Postretirement Benefits [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherPostretirementBenefitPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCash [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CashMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse40false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse10000001falsetruefalsefalsefalse2truefalsefalse30000003falsetruefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d(iv)(b)(i)
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 49
falsefalse1For U.S. and non-U.S. equity securities held in the form of fund units that are redeemable at the measurement date, the unit value is treated as a Level 2 input. The fair value of the securities owned by the funds is based on observable quoted prices on active exchanges, which are Level 1 inputs. 2For corporate, government and asset-backed debt securities, fair value is based on observable inputs of comparable market transactions. 3For private equity, fair value is generally established by using revenue or earnings multiples or other relevant market data including Initial Public Offerings. 4For private mortgages, fair value is based on proprietary credit spread matrices developed using market data and monthly surveys of active mortgage bankers. 339Pension and Other Postretirement Benefits (Fair Value of Benefit Plan Assets- Other Postretirement) (Details) (Other Postretirement Benefits [Member], USD $)MillionsUnKnownUnKnownUnKnownfalsetrue