2.2.0.25truefalse41901 - Disclosure - Employee Benefits (Narrative) (Details)truefalseIn Millions, unless otherwise specifiedfalse1falsefalseUSDfalsefalse1/1/2010 - 12/31/2010
USD ($)
USD ($) / shares
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USD ($)
USD ($) / shares
$Duration_1_1_2009_To_12_31_2009http://www.sec.gov/CIK0000093751duration2009-01-01T00:00:002009-12-31T00:00:00Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$3falsefalseUSDfalsefalse1/1/2008 - 12/31/2008
USD ($)
USD ($) / shares
$Duration_1_1_2008_To_12_31_2008http://www.sec.gov/CIK0000093751duration2008-01-01T00:00:002008-12-31T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$4falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans, Defined Benefit [Member]
1/1/2011 - 12/31/2011
USD ($)
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itPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans, Defined Benefit [Member]
1/1/2010 - 12/31/2010
USD ($)
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itPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans, Defined Benefit [Member]
1/1/2009 - 12/31/2009
USD ($)
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itPlansDisclosuresDefinedBenefitPlansAxis} : United States Pension Plans of US Entity, Defined Benefit [Member]
12/31/2010
USD ($)
$As_Of_12_31_20106http://www.sec.gov/CIK0000093751instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseUnited States Pension Plans of US Entity, Defined Benefit [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$8falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : United States Pension Plans of US Entity, Defined Benefit [Member]
12/31/2009
USD ($)
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1/1/2011 - 12/31/2011
USD ($)
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rg/2003/iso4217USDiso42170USDUSD$10falsefalseUSDtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Postretirement Benefit Plans, Defined Benefit [Member]
1/1/2011 - 12/31/2011
USD ($)
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it12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$11falsefalseUSDtruefalse{us-gaap_DeferredCompensationArrangementWithIndividualPostretirementBenefitsByTypeOfDeferredCompensationAxis} : Accumulated Defined Benefit Plans Adjustment [Member]
12/31/2010
USD ($)
$As_Of_12_31_2010828http://www.sec.gov/CIK0000093751instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseAccumulated Defined Benefit Plans Adjustment [Member]us-gaap_DeferredCompensationArrangementWithIndividualPostretirementBenefitsByTypeOfDeferredCompensationAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap_DeferredCompensationArrangementWithIndividualPostretirementBenefitsByTypeOfDeferredCompensationAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$12falsefalseUSDtruefalse{us-gaap_DeferredCompensationArrangementWithIndividualPostretirementBenefitsByTypeOfDeferredCompensationAxis} : Accumulated Defined Benefit Plans Adjustment [Member]
12/31/2009
USD ($)
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lans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph e
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 264
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Name Statement of Financial Accounting Standard (FAS)
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