Annual report pursuant to Section 13 and 15(d)

BENEFIT PLANS (Fair Value of Pension Assets) (Detail)

v2.4.1.9
BENEFIT PLANS (Fair Value of Pension Assets) (Detail) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]      
Hedge funds, minimum number of days notice prior to redemption 30 days    
Hedge funds, maximum number of days notice prior to redemption 90 days    
Private Equity      
Defined Benefit Plan Disclosure [Line Items]      
Commitments related to investments 19.8us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted
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Real Assets      
Defined Benefit Plan Disclosure [Line Items]      
Commitments related to investments 3.0us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted
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Pension Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 570.1us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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548.0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Pension Benefits | Large-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 115.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Pension Benefits | Small- and Mid-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 28.9us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Pension Benefits | International Equity      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 94.7us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Pension Benefits | Fixed Income      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 181.3us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Pension Benefits | Private Equity      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 35.7us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Pension Benefits | Hedge Funds      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 69.7us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Pension Benefits | Real Assets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 36.7us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Pension Benefits | Cash      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 7.5us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 199.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits | Large-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 115.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits | Small- and Mid-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 28.9us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits | International Equity      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 15.9us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits | Fixed Income      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 11.7us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits | Private Equity      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits | Hedge Funds      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits | Real Assets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 20.2us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Benefits | Cash      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 7.5us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Other Observable Inputs (Level 2) | Pension Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 248.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Other Observable Inputs (Level 2) | Pension Benefits | Large-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Other Observable Inputs (Level 2) | Pension Benefits | Small- and Mid-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Other Observable Inputs (Level 2) | Pension Benefits | International Equity      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 78.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Other Observable Inputs (Level 2) | Pension Benefits | Fixed Income      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 169.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Other Observable Inputs (Level 2) | Pension Benefits | Private Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Other Observable Inputs (Level 2) | Pension Benefits | Hedge Funds      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Other Observable Inputs (Level 2) | Pension Benefits | Real Assets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Other Observable Inputs (Level 2) | Pension Benefits | Cash      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Unobservable Inputs (Level 3) | Pension Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 121.9us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Unobservable Inputs (Level 3) | Pension Benefits | Large-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Unobservable Inputs (Level 3) | Pension Benefits | Small- and Mid-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Unobservable Inputs (Level 3) | Pension Benefits | International Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Unobservable Inputs (Level 3) | Pension Benefits | Fixed Income      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Unobservable Inputs (Level 3) | Pension Benefits | Private Equity      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 35.7us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Unobservable Inputs (Level 3) | Pension Benefits | Hedge Funds      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 69.7us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Significant Unobservable Inputs (Level 3) | Pension Benefits | Real Assets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 16.5us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan Disclosure [Line Items]      
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