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PENSION AND OTHER POSTRETIREMENT BENEFITS (Estimated Future Benefit Payments) (Details) $ in Millions | Dec. 31, 2019 USD ($)
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Pension Plan [Member] |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
2020 | $ 73.6
2021 | 71.1
2022 | 70.4
2023 | 71.2
2024 | 66.9
2025 | 318.2
Other Postretirement Benefits Plan [Member] |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
2020 | 16.5
Medicare Subsidy - 2020 | (0.7)
2021 | 15.8
Medicare Subsidy - 2021 | (0.8)
2022 | 15.5
Medicare Subsidy - 2022 | (0.8)
2023 | 15.5
Medicare Subsidy - 2023 | (0.8)
2024 | 15.2
Medicare Subsidy - 2024 | (0.9)
2025 | 72.7
Medicare Subsidy - 2025 | (4.6)
Gross Company Benefits [Member] | Other Postretirement Benefits Plan [Member] |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
2020 | 17.2
2021 | 16.6
2022 | 16.3
2023 | 16.3
2024 | 16.1
2025 | $ 77.3

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