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SEGMENT REPORTING (Schedule of Segment Reporting Information) (Details) T in Thousands, $ in Millions | 1 Months Ended | 3 Months Ended
--- | --- | ---
Mar. 31, 2020 USD ($) | Mar. 31, 2020 USD ($) unit T | Mar. 31, 2019 USD ($) T
Segment Reporting Information [Line Items] |  |  |  |  |
Number of Reporting Units | unit |  |  | 2 |  |
Revenues | [1] |  | $ 359.1 |  | $ 157.0
Realization of deferred revenue |  |  | 34.6 |  | 0.0
Net loss |  |  | (48.6) |  | (22.1)
Interest expense, net |  |  | (31.0) |  | (25.1)
Income tax benefit |  |  | 51.4 |  | 3.7
Depreciation, depletion and amortization |  |  | (34.4) |  | (19.9)
EBITDA |  |  | (34.5) |  | 19.2
Acquisition-related costs |  |  | (42.5) |  | 0.0
Gain (loss) on extinguishment of debt |  |  | 3.2 |  | (0.3)
Impact of discontinued operations |  |  | 0.6 |  | 0.0
Adjusted EBITDA |  |  | 22.7 |  | 21.2
Net Income (Loss) Attributable to Noncontrolling Interest |  |  | 3.5 |  | 0.0
Depreciation, Depletion and Amortization Attributable to Noncontrolling Interests |  |  | 1.1 |  |
Property, Plant and Equipment, Additions |  |  | $ 157.7 |  | $ 129.3
Steel and Manufacturing [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Sales Volume (Net Tons) | T |  |  | 199 |  | 0
Revenues |  |  | $ 217.5 |  | $ 0.0
Adjusted EBITDA |  |  | (11.1) |  | (0.8)
Property, Plant and Equipment, Additions | [2] |  | $ 122.9 |  | $ 82.4
Mining and Pelletizing [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Sales Volume (Long Tons) | T |  |  | 1,351 |  | 1,550
Revenues |  |  | $ 141.6 |  | $ 157.0
Adjusted EBITDA |  |  | 81.8 |  | 47.5
Property, Plant and Equipment, Additions |  |  | 34.2 |  | 46.8
Corporate and Other [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Adjusted EBITDA |  |  | (48.0) |  | (25.5)
Property, Plant and Equipment, Additions |  |  | $ 0.6 |  | $ 0.1
Operating Segments [Member] | Mining and Pelletizing [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Sales Volume (Long Tons) | T |  |  | 2,134 |  | 1,550
Revenues |  |  | $ 229.4 | [3] | $ 157.0
Intersegment Eliminations [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Revenues |  |  | $ 67.8 |  | $ 67.4
Intersegment Eliminations [Member] | Mining and Pelletizing [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Sales Volume (Long Tons) | T |  |  | (783) |  | 0
Revenues |  |  | $ (87.8) |  | $ 0.0
EBITDA Calculation [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Interest expense, net |  |  | (31.1) |  | (25.1)
Income tax benefit |  |  | 51.4 |  | 3.7
Depreciation, depletion and amortization |  |  | (34.4) |  | (19.9)
Adjusted EBITDA Calculation [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
EBITDA of Noncontrolling Interests |  |  | 4.6 | [4] | 0.0
Severance costs |  |  | (19.3) |  | (1.7)
Gain (loss) on extinguishment of debt |  |  | 3.2 |  | (0.3)
Impact of discontinued operations |  |  | 0.7 |  | 0.0
AK Steel Holding Corporation [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Revenues |  | $ 217.5 |  |  |
Severance costs |  | (17.6) |  |  |
AK Steel Holding Corporation [Member] | Adjusted EBITDA Calculation [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Acquisition-related costs |  |  | $ (23.2) |  | 0.0
Amortization of Inventory Step-up |  | $ (23.2) |  |  | $ 0.0
[1] | 1 Includes Realization of deferred revenue of $34.6 million for the three months ended March 31, 2020.
[2] | 1 Refer to NOTE 2 - SUPPLEMENTARY FINANCIAL STATEMENT INFORMATION for additional information.
[3] | 1 Includes Realization of deferred revenue of $34.6 million for the three months ended March 31, 2020.
[4] | 1 Includes $3.5 million of income attributable to noncontrolling interests and $1.1 million of depreciation, depletion and amortization for the three months ended March 31, 2020.

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