Annual report pursuant to Section 13 and 15(d)

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

v2.4.1.9
BENEFIT PLANS (Fair Value of Postretirement Assets) (Detail) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]      
Hedge funds, minimum number of days notice prior to redemption 30 days    
Hedge funds, maximum number of days notice prior to redemption 90 days    
Other Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 20.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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$ 21.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Other Benefits | Large-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Other Benefits | Small- and Mid-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Other Benefits | International Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Other Benefits | Fixed Income      
Defined Benefit Plan Disclosure [Line Items]      
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Other Benefits | Private Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Other Benefits | Hedge Funds      
Defined Benefit Plan Disclosure [Line Items]      
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Other Benefits | Real Assets      
Defined Benefit Plan Disclosure [Line Items]      
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Other Benefits | Cash      
Defined Benefit Plan Disclosure [Line Items]      
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Benefits      
Defined Benefit Plan Disclosure [Line Items]      
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Benefits | Large-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Benefits | Small- and Mid-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Benefits | International Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Benefits | Fixed Income      
Defined Benefit Plan Disclosure [Line Items]      
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Benefits | Private Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Benefits | Hedge Funds      
Defined Benefit Plan Disclosure [Line Items]      
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Benefits | Real Assets      
Defined Benefit Plan Disclosure [Line Items]      
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Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Benefits | Cash      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Other Observable Inputs (Level 2) | Other Benefits      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Other Observable Inputs (Level 2) | Other Benefits | Large-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Other Observable Inputs (Level 2) | Other Benefits | Small- and Mid-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Other Observable Inputs (Level 2) | Other Benefits | International Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Other Observable Inputs (Level 2) | Other Benefits | Fixed Income      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Other Observable Inputs (Level 2) | Other Benefits | Private Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Other Observable Inputs (Level 2) | Other Benefits | Hedge Funds      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Other Observable Inputs (Level 2) | Other Benefits | Real Assets      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Other Observable Inputs (Level 2) | Other Benefits | Cash      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Unobservable Inputs (Level 3) | Other Benefits      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Unobservable Inputs (Level 3) | Other Benefits | Large-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Unobservable Inputs (Level 3) | Other Benefits | Small- and Mid-Cap Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Unobservable Inputs (Level 3) | Other Benefits | International Equity      
Defined Benefit Plan Disclosure [Line Items]      
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Significant Unobservable Inputs (Level 3) | Other Benefits | Fixed Income      
Defined Benefit Plan Disclosure [Line Items]      
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Defined Benefit Plan Disclosure [Line Items]      
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Defined Benefit Plan Disclosure [Line Items]      
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Significant Unobservable Inputs (Level 3) | Other Benefits | Real Assets      
Defined Benefit Plan Disclosure [Line Items]      
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