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PENSIONS AND OTHER POSTRETIREMENT BENEFITS PENSION AND POST RETIREMENT BENEFITS (Components of Accumulated Other Comprehensive Loss (Income) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | $ 50.8 | $ 11.1
Actual returns on assets (over) under estimate | (43.5) | 89.6
Amortization of net actuarial loss | (23.5) | (21.2)
Amortization of prior service credit (cost) | (1.2) | (2.2)
Current year prior service cost | 0.0 | 2.2
Other | 7.2 | (0.3)
Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | (7.5) | 9.5
Actual returns on assets (over) under estimate | (18.3) | 26.6
Amortization of net actuarial loss | (5.1) | (5.0)
Amortization of prior service credit (cost) | 2.0 | 3.0
Current year prior service cost | 0.0 | 12.8
Other | (5.0) | 1.5
Change in Assumptions for Defined Benefit Plans, Discount Rates [Member] | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | 105.8 | (75.7)
Change in Assumptions for Defined Benefit Plans, Discount Rates [Member] | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | 25.5 | (19.0)
Change in Assumptions for Defined Benefit Plans, Demographic [Member] | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | 12.3 | 21.7
Change in Assumptions for Defined Benefit Plans, Demographic [Member] | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | 3.6 | 2.3
Changes in Assumptions for Defined Benefit Plans, Mortality [Member] | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | (6.3) | (3.0)
Changes in Assumptions for Defined Benefit Plans, Mortality [Member] | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | (3.9) | (0.8)
Changes in Assumptions for Defined Benefit Plans, Per Capita Claims [Member] | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | 0.0 | 0.0
Changes in Assumptions for Defined Benefit Plans, Per Capita Claims [Member] | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | (9.4) | (11.9)
Changes in Assumptions for Defined Benefit Plans, Other Actuarial (Gain) Loss [Member] | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | 0.0 | 0.0
Changes in Assumptions for Defined Benefit Plans, Other Actuarial (Gain) Loss [Member] | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | 3.1 | 0.0
Changes in Assumptions for Defined Benefit Plans, Actuarial (Gain) Loss [Member] | Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | 111.8 | (57.0)
Changes in Assumptions for Defined Benefit Plans, Actuarial (Gain) Loss [Member] | Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, (Gain) Loss Arising During Period, before Tax | $ 18.9 | $ (29.4)

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