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DEBT AND CREDIT FACILITIES (Debt Extinguishment) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Extinguishment of Debt [Line Items] |  |  |
Debt Extinguished | $ 724.0 | $ 227.4 | $ 1,610.7
Gain (loss) on extinguishment of debt | (18.2) | (6.8) | (165.4)
Debt redemption premiums paid | (5.3) | (7.1) | (110.0)
$700 Million 4.875% 2021 Senior Notes [Member] |  |  |
Extinguishment of Debt [Line Items] |  |  |
Debt Extinguished | 124.0 | 14.4 | 171.0
Gain (loss) on extinguishment of debt | $ (5.3) | 0.1 | (2.8)
$1.075 Billion 5.75% 2025 Senior Notes [Member] |  |  |
Extinguishment of Debt [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 5.75% |  |
Debt Extinguished | $ 600.0 | 1.7 |
Gain (loss) on extinguishment of debt | $ (12.9) | 0.1 |
$400 Million 5.90% 2020 Senior Notes |  |  |
Extinguishment of Debt [Line Items] |  |  |
Debt Extinguished |  | 88.9 | 136.7
Gain (loss) on extinguishment of debt |  | (3.3) | (7.8)
$540 Million 8.25% 2020 First Lien Notes |  |  |
Extinguishment of Debt [Line Items] |  |  |
Debt Extinguished |  |  | 540.0
Gain (loss) on extinguishment of debt |  |  | (93.5)
$218.5 Million 8.00% 2020 1.5 Lien Notes |  |  |
Extinguishment of Debt [Line Items] |  |  |
Debt Extinguished |  |  | 218.5
Gain (loss) on extinguishment of debt |  |  | 45.1
$544.2 Million 7.75% 2020 Second Lien Notes |  |  |
Extinguishment of Debt [Line Items] |  |  |
Debt Extinguished |  |  | 430.1
Gain (loss) on extinguishment of debt |  |  | (104.5)
$500 Million 4.80% 2020 Senior Notes |  |  |
Extinguishment of Debt [Line Items] |  |  |
Debt Extinguished |  | 122.4 | 114.4
Gain (loss) on extinguishment of debt |  | $ (3.7) | $ (1.9)
$800 Million 6.25% 2040 Senior Notes [Member] |  |  |
Extinguishment of Debt [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 6.25% |  |

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