Annual report pursuant to Section 13 and 15(d)

PENSIONS AND OTHER POSTRETIREMENT BENEFITS PENSIONS AND OTHER POSTRETIREMENT BENEFITS (Unobservable Inputs, Level 3) (Details)

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12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Defined Benefit Plan, Fair Value of Plan Assets $ 205.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets $ 188.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets $ 200.5us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
Defined Benefit Plan, Actual Return on Plan Assets Still Held 15.9us-gaap_DefinedBenefitPlanActualReturnOnPlanAssetsStillHeld 41.0us-gaap_DefinedBenefitPlanActualReturnOnPlanAssetsStillHeld  
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Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets 6.8us-gaap_DefinedBenefitPlanBusinessCombinationsAndAcquisitionsPlanAssets 145.0us-gaap_DefinedBenefitPlanBusinessCombinationsAndAcquisitionsPlanAssets  
Defined Benefit Plan, Divestitures, Plan Assets (7.0)us-gaap_DefinedBenefitPlanDivestituresPlanAssets (172.8)us-gaap_DefinedBenefitPlanDivestituresPlanAssets  
Other Postretirement Benefit Plan, Defined Benefit [Member]      
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Private Equity Funds [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
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Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
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Fair Value, Inputs, Level 3 [Member] | betfred reviewsReal Estate [Member] | Other Postretirement Benefit Plan, Defined Benefit [Member]      
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