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PENSION AND OTHER POSTRETIREMENT BENEFITS (Estimated Future Benefit Payments) (Details) $ in Millions | Dec. 31, 2017 USD ($)
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Pension Benefits [Member] |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
2017 | $ (69.6)
2018 | (66.7)
2019 | (66.0)
2020 | (65.1)
2021 | (65.2)
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter | (310.5)
Gross Company Benefits [Member] |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
2017 | (18.9)
2018 | (18.0)
2019 | (17.4)
2020 | (16.9)
2021 | (16.7)
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter | (81.5)
Less Medicare Subsidy [Member] |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
2017 | (0.7)
2018 | (0.8)
2019 | (0.9)
2020 | (1.0)
2021 | (1.1)
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter | (6.6)
Net Company Payments [Member] |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
2017 | (18.2)
2018 | (17.2)
2019 | (16.5)
2020 | (15.9)
2021 | (15.6)
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter | $ (74.9)

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