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DEBT AND CREDIT FACILITIES DEBT AND CREDIT FACILITIES (Schedule of Extinguishment of Debt) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
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Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Extinguishment of Debt [Line Items] |  |  |
Extinguishment of Debt, Amount | $ 1.0 | $ 724.0 | $ 16.5
Gain (loss) on extinguishment of debt | 0.0 | (18.2) | 0.2
$400 million 5.90% 2020 Senior Notes [Member] |  |  |
Extinguishment of Debt [Line Items] |  |  |
Extinguishment of Debt, Amount | 0.0 |  | 0.5
Gain (loss) on extinguishment of debt | 0.0 |  | 0.0
$500 Million 4.80% 2020 Senior Notes [Member] |  |  |
Extinguishment of Debt [Line Items] |  |  |
Extinguishment of Debt, Amount | 0.0 |  | 0.1
Gain (loss) on extinguishment of debt | 0.0 |  | 0.0
$700 Million 4.875% 2021 Senior Notes [Member] |  |  |
Extinguishment of Debt [Line Items] |  |  |
Extinguishment of Debt, Amount | 1.0 | 124.0 | 14.2
Gain (loss) on extinguishment of debt | 0.0 | (5.3) | 0.1
$1.075 Billion 5.75% 2025 Senior Notes [Member] |  |  |
Extinguishment of Debt [Line Items] |  |  |
Extinguishment of Debt, Amount | 0.0 | 600.0 | 1.7
Gain (loss) on extinguishment of debt | $ 0.0 | $ (12.9) | $ 0.1

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