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DEBT AND CREDIT FACILITIES (Debt Extinguishment) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Mar. 31, 2017 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Extinguishment of Debt [Line Items] |  |  |  |  |  |
Extinguishment of Debt, Amount |  |  |  | $ 1,610.7 |  |
Gain (loss) on extinguishment/restructuring of debt |  |  | $ 174.3 | (165.4) | $ 166.3 | $ 392.9
$540 Million 8.25% 2020 First Lien Notes [Member] |  |  |  |  |  |
Extinguishment of Debt [Line Items] |  |  |  |  |  |
Extinguishment of Debt, Amount |  | $ 35.6 |  | 540.0 |  |
Gain (loss) on extinguishment/restructuring of debt |  |  |  | (93.5) |  |
$218.5 Million 8.00% 2020 1.5 Lien Notes [Member] |  |  |  |  |  |
Extinguishment of Debt [Line Items] |  |  |  |  |  |
Extinguishment of Debt, Amount |  |  |  | 218.5 |  |
Gain (loss) on extinguishment/restructuring of debt |  |  |  | 45.1 |  |
$544.2 Million 7.75% 2020 Second Lien Notes [Member] |  |  |  |  |  |
Extinguishment of Debt [Line Items] |  |  |  |  |  |
Extinguishment of Debt, Amount |  |  |  | 430.1 |  |
Gain (loss) on extinguishment/restructuring of debt |  |  |  | (104.5) | 6.9 |
Four Hundred Million Five Point Nine Zero Two Thousand And Twenty Senior Note [Member] |  |  |  |  |  |
Extinguishment of Debt [Line Items] |  |  |  |  |  |
Extinguishment of Debt, Amount |  |  |  | 136.7 |  |
Gain (loss) on extinguishment/restructuring of debt |  |  |  | (7.8) | 28.3 |
$500 Million 4.80% 2020 Senior Notes[Member] |  |  |  |  |  |
Extinguishment of Debt [Line Items] |  |  |  |  |  |
Extinguishment of Debt, Amount |  |  |  | 114.4 |  |
Gain (loss) on extinguishment/restructuring of debt | $ 0.6 |  |  | (1.9) | 19.5 |
$700 Million 4.875% 2021 Senior Notes[Member] |  |  |  |  |  |
Extinguishment of Debt [Line Items] |  |  |  |  |  |
Extinguishment of Debt, Amount |  |  |  | 171.0 |  |
Gain (loss) on extinguishment/restructuring of debt |  |  |  | $ (2.8) | $ 33.3 |

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- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629 + Details
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