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DEBT AND CREDIT FACILITIES DEBT AND CREDIT FACILITIES (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018 | Dec. 31, 2018
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Par Value |  | $ 2,238.0 |  |
Extinguishment of Debt, Amount | $ 1.0 | 724.0 | $ 16.5 |
$750 Million 5.875% 2027 Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Par Value |  | $ 750.0 |  |
Debt issuance, discount rate |  | 96.125% |  |
Debt Instrument, Interest Rate, Stated Percentage |  | 5.875% |  |
Repurchase price if triggering event occurs |  | 101.00% |  |
Debt Issuance Costs, Gross |  | $ 6.8 |  |
$1.075 Billion 5.75% 2025 Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Par Value |  | 473.3 |  | $ 1,073.3
Extinguishment of Debt, Amount | $ 0.0 | $ 600.0 | $ 1.7 |

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