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PENSIONS AND OTHER POSTRETIREMENT BENEFITS (Narrative) (Details) - USD ($) |  |  | 12 Months Ended
--- | --- | --- | ---
Jan. 01, 2019 | Oct. 12, 2018 | Dec. 31, 2018 | Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Term Of Agreement |  | 4 years |  |
401(k) contribution match |  |  | $ 0.50 |
Defined Benefit Plan, Accumulated Benefit Obligation |  |  | 896,800,000 | $ 963,000,000
Reserve for investment commitments |  |  | 44,200,000 |
Early Termination Fees for Pension Benefits |  |  | 22,100,000 |
Early Termination Fees for Other Postretirement Benefits |  |  | $ 3,400,000 |
Structured Finance [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Redemption request notice period, days |  |  | 90 days |
Real Estate [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Redemption request notice period, days |  |  | 45 days |
Withdrawal request notice period, days |  |  | 65 days |
Pension Benefits [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Decrease in Projected Benefit Obligation due to Market Conditions |  |  | $ 75,700,000 | (46,100,000)
Increase in Projected Benefit Obligation due to new mortality tables |  |  | (21,700,000) | 6,100,000
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) |  |  | (57,000,000) | 54,600,000
Other Benefits [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Plan Assets, Contributions by Plan Participants |  |  | 5,600,000 | 4,600,000
Decrease in Projected Benefit Obligation due to Market Conditions |  |  | 19,000,000 | (12,600,000)
Increase in Projected Benefit Obligation due to new mortality tables |  |  | (2,300,000) | 1,900,000
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) |  |  | (29,400,000) | $ 7,400,000
Prior To Age65 [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Annual limit on medical coverage for each participant |  |  | 7,000 |
Subsequent Event [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
401(k) contribution match | $ 0.60 |  |  |
Adoption of New Projection Scale [Member] | Pension Benefits [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Increase in Projected Benefit Obligation due to new mortality tables |  |  | 3,000,000 |
Adoption of New Projection Scale [Member] | Other Benefits [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Increase in Projected Benefit Obligation due to new mortality tables |  |  | 800,000 |
Update Assumption per Capita Cost [Member] | Other Benefits [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Increase in Projected Benefit Obligation due to new mortality tables |  |  | $ 11,900,000 |

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