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Defined Benefit Postretirement Plans and Defined Contribution Plan (Details 6) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2015
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]        
Pension Contributions $ 24us-gaap_PensionContributions $ 26us-gaap_PensionContributions $ 25us-gaap_PensionContributions  
Scenario, Forecast [Member]        
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]        
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year       11us-gaap_DefinedBenefitPlansEstimatedFutureEmployerContributionsInNextFiscalYear
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United States Pension Plans of US Entity, Defined Benefit [Member]        
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]        
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months 80us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
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Defined Benefit Plan, Expected Future Benefit Payments, Year Three 83us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree
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Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter 299us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter
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Foreign Pension Plans, Defined Benefit [Member]        
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]        
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months 15us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
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Other Postretirement Benefit Plans, Defined Benefit [Member]        
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]        
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months 19us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
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Defined Benefit Plan, Expected Future Benefit Payments, Year Five 19us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive
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Other Postretirement Benefit Plans, Defined Benefit [Member] | Scenario, Forecast [Member]        
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]        
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year       19us-gaap_DefinedBenefitPlansEstimatedFutureEmployerContributionsInNextFiscalYear
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Unfunded Plans [Member] | Scenario, Forecast [Member]        
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]        
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year       $ 95us-gaap_DefinedBenefitPlansEstimatedFutureEmployerContributionsInNextFiscalYear
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