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PENSION AND OTHER POSTRETIREMENT BENEFITS (Estimated Future Benefit Payments) (Details) $ in Millions | Dec. 31, 2018 USD ($)
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Pension Benefits [Member] |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
2017 | $ (70.4)
2018 | (67.9)
2019 | (67.5)
2020 | (67.0)
2021 | (67.9)
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter | (309.7)
Gross Company Benefits [Member] |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
2017 | (18.0)
2018 | (17.7)
2019 | (17.2)
2020 | (17.0)
2021 | (16.9)
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter | (82.2)
Less Medicare Subsidy [Member] |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
2017 | (0.8)
2018 | (0.8)
2019 | (0.9)
2020 | (0.9)
2021 | (1.0)
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter | (5.4)
Net Company Payments [Member] |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
2017 | (17.2)
2018 | (16.9)
2019 | (16.3)
2020 | (16.1)
2021 | (15.9)
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter | $ (76.8)

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