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CAPITAL STOCK (Details) $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2016 USD ($) $ / shares shares | Sep. 30, 2016 USD ($) | Dec. 31, 2015 USD ($) $ / shares shares | Sep. 30, 2015 USD ($) | Jun. 30, 2015 USD ($) | Mar. 31, 2015 USD ($) | Feb. 11, 2013 | Sep. 30, 2016 USD ($) | Dec. 31, 2016 USD ($) $ / shares shares | Dec. 31, 2015 USD ($) $ / shares shares | Dec. 31, 2014 USD ($) | Aug. 10, 2016 $ / shares | Mar. 31, 2016 USD ($) | Nov. 02, 2015 $ / shares | Aug. 03, 2015 $ / shares | May 01, 2015 $ / shares | Feb. 02, 2015 $ / shares | Jan. 26, 2015 $ / shares | Dec. 03, 2014 $ / shares | Nov. 03, 2014 $ / shares | Sep. 02, 2014 $ / shares | Aug. 01, 2014 $ / shares | Jun. 03, 2014 $ / shares | Mar. 03, 2014 $ / shares
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment/restructuring of debt |  |  |  |  |  |  |  |  | $ 166.3 | $ 392.9 | $ 16.2 |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, New Shares, Issued | shares |  |  |  |  |  |  |  |  | 44,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Depositary Share Interest in a Share of 7% Series A Mandatory Convertible Preferred Stock, Class A |  |  |  |  |  |  |  |  | 0.025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Par or Stated Value Per Share | $ / shares | $ 0.125 |  | $ 0.125 |  |  |  |  |  | $ 0.125 | $ 0.125 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Trading Day Window Determining Number of Common Shares Issuable on Conversion |  |  |  |  |  |  |  |  | 20 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends, Preferred Stock |  |  |  |  |  |  |  |  | $ 0.0 | $ 38.4 | 51.2 |  |  |  |  |  |  |  |  |  |  |  |  |
Common shares, issued (in shares) | shares | 238,636,794 |  | 159,546,224 |  |  |  |  |  | 238,636,794 | 159,546,224 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds from issuance of common shares |  |  |  |  |  |  |  | $ 287.6 | $ 287.4 | $ 0.0 | 0.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Elimination of Dividend | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.15 |  |  |  |  |  |
Current Fiscal Year End Date |  |  |  |  |  |  |  |  | --12-31 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Shares Issued in Debt to Equity Exchange | shares | 8,200,000 |  |  |  |  |  |  |  | 8,200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount Exchanged |  |  |  |  |  | $ 674.6 |  |  |  |  |  |  | $ 512.2 |  |  |  |  |  |  |  |  |  |  |
Shares Issued, Price Per Share | $ / shares |  |  |  |  |  |  |  |  |  |  |  | $ 6.75 |  |  |  |  |  |  |  |  |  |  |  |
Preferred Class A [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred Stock, Liquidation Preference Per Share | $ / shares | $ 1,000 |  | $ 1,000 |  |  |  |  |  | $ 1,000 | $ 1,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends payable, per share | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 17.5000 | $ 0.44 | $ 17.50 | $ 0.44 |  |  | $ 17.5000 |  | $ 0.44 |  |
Dividends, Preferred Stock |  |  | $ 0.0 | $ 25.6 | $ 0.0 | 12.8 |  |  | $ 0.0 | $ 38.4 | $ 51.2 |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible Preferred Stock, Common Shares Issued Upon Conversion in Lieu of Dividend | shares | 1,300,000 |  |  |  |  |  |  |  | 1,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible Preferred Stock, Shares Issued upon Conversion | shares | 0.7037 |  |  |  |  |  |  |  | 0.7037 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible Preferred Stock, Shares Issued Upon Conversion per Depositary Share | shares | 0.9052 |  |  |  |  |  |  |  | 0.9052 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends payable, per share | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.150 |  | $ 0.150 |  | $ 0.150 | $ 0.150
Increase Decrease In Dividends Payable Percentage |  |  |  |  |  |  | 76.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common shares, issued (in shares) | shares | 26,500,000.0000 |  |  |  |  |  |  |  | 26,500,000.0000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible Preferred Stock, Common Shares Issued Upon Conversion | shares | 25,200,000.0000 |  |  |  |  |  |  |  | 25,200,000.0000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible Preferred Stock, Shares Issued upon Conversion | shares | 28.1480 |  |  |  |  |  |  |  | 28.1480 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible Preferred Stock, Shares Issued Upon Conversion per Depositary Share | shares | 0.8621 |  |  |  |  |  |  |  | 0.8621 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible Preferred Stock, Shares Issued upon Conversion | shares | 34.4840 |  |  |  |  |  |  |  | 34.4840 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Depositary Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends payable, per share | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.44 | $ 17.5000 | $ 0.44 | $ 17.5000 |  |  | $ 0.44 |  | $ 17.5000 |  |
Exchange of Debt for Equity [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment/restructuring of debt | $ 11.3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
$500 Million 3.95% 2018 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment/restructuring of debt |  | $ (19.9) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount Exchanged |  |  |  |  |  |  |  |  |  |  |  |  | 17.6 |  |  |  |  |  |  |  |  |  |  |
$500 Million 3.95% 2018 Senior Notes [Member] | Exchange of Debt for Equity [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount Exchanged | 10.0 |  |  |  |  |  |  |  | $ 10.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
$218.5 Million 8.00% 2020 1.5 Lien Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount Received in Debt Exchange of $500M 3.95% Notes |  |  |  |  |  |  |  |  |  |  |  |  | 11.4 |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount Received in Debt Exchange of $500M 4.80% Notes |  |  |  |  |  |  |  |  |  |  |  |  | 17.9 |  |  |  |  |  |  |  |  |  |  |
Debt instrument, Face Amount Received in Debt Exchange of $700M 4.875% Notes |  |  |  |  |  |  |  |  |  |  |  |  | 30.5 |  |  |  |  |  |  |  |  |  |  |
$218.5 Million 8.00% 2020 1.5 Lien Notes [Member] | Exchange of Debt for Equity [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount Exchanged | 20.1 |  |  |  |  |  |  |  | 20.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
$700 Million 4.875% 2021 Senior Notes[Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount Exchanged |  |  |  |  |  | $ 208.5 |  |  |  |  |  |  | $ 76.3 |  |  |  |  |  |  |  |  |  |  |
$700 Million 4.875% 2021 Senior Notes[Member] | Exchange of Debt for Equity [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount Exchanged | $ 26.8 |  |  |  |  |  |  |  | $ 26.8 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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