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DEBT AND CREDIT FACILITIES DEBT AND CREDIT FACILITIES (Schedule of Extinguishment of Debt) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Extinguishment of Debt [Line Items] |  |  |  |
Extinguishment of Debt, Amount | $ 714.0 | $ 15.5 | $ 724.0 | $ 15.5
Gain (loss) on extinguishment of debt | 17.9 | (0.2) | 18.2 | (0.2)
$700 Million 4.875% 2021 Senior Notes [Member] |  |  |  |
Extinguishment of Debt [Line Items] |  |  |  |
Extinguishment of Debt, Amount | 114.0 | 13.2 | 124.0 | 13.2
Gain (loss) on extinguishment of debt | (5.0) | (0.1) | (5.3) | (0.1)
$1.075 Billion 5.75% 2025 Senior Notes [Member] |  |  |  |
Extinguishment of Debt [Line Items] |  |  |  |
Extinguishment of Debt, Amount | 600.0 | 1.7 | 600.0 | 1.7
Gain (loss) on extinguishment of debt | $ (12.9) | (0.1) | $ (12.9) | (0.1)
$400 million 5.90% 2020 Senior Notes [Member] |  |  |  |
Extinguishment of Debt [Line Items] |  |  |  |
Extinguishment of Debt, Amount |  | 0.5 |  | 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 |  | 0.1 |  | 0.1
Gain (loss) on extinguishment of debt |  | $ 0.0 |  | $ 0.0

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