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QUARTERLY RESULTS OF OPERATIONS (Details) - USD ($) shares in Millions, $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2016 | Sep. 30, 2016 | Dec. 31, 2015 | Mar. 31, 2014 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount |  |  |  |  |  | 25.3 | 25.2
Antidilutive Incremental Common Shares Excluded and Attributable to Share-based Payment Arrangements | 0.0 | 3.0 |  |  |  |  | 0.7
Loss (gain) on sale of North American Coal mines |  |  |  | $ 155.0 |  |  |
Sale Price of CLCC Assets |  |  |  | $ 174.0 |  |  |
Income Tax Expense (Benefit) |  |  |  |  | $ (12.2) | $ 169.3 | $ (86.0)
Asset Impairment Charges |  |  |  |  | $ 0.0 | $ 3.3 | $ 635.5
Minimum [Member] |  |  |  |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount |  |  | 25.2 |  |  |  |
Antidilutive Incremental Common Shares Excluded and Attributable to Share-based Payment Arrangements |  |  | 0.1 |  |  |  |
Maximum [Member] |  |  |  |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount |  |  |  |  |  | 25.6 |
Antidilutive Incremental Common Shares Excluded and Attributable to Share-based Payment Arrangements |  |  |  |  |  | 0.3 |

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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Antidilution -URI http://asc.fasb.org/extlink&oid=6505113 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Diluted Earnings Per Share -URI http://asc.fasb.org/extlink&oid=6510752 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Contingent Stock Agreement -URI http://asc.fasb.org/extlink&oid=6508534 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228 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=66902209&loc=d3e3602-108585 + Details
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