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SEGMENT REPORTING (Schedule Of Segment Reporting Information, By Segment) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues from product sales and services | $ 600.9 | $ 698.4 | $ 569.3 | $ 461.6 | $ 754.0 | $ 553.3 | $ 496.2 | $ 305.5 | $ 2,330.2 | $ 2,109.0 | $ 2,013.3
Revenues from producet sales and services, percent |  |  |  |  |  |  |  |  | 100.00% | 100.00% | 100.00%
SALES MARGIN | $ 100.7 | $ 160.2 | $ 145.1 | $ 95.7 | $ 181.5 | $ 85.4 | $ 91.5 | 30.9 | $ 501.7 | $ 389.3 | $ 236.5
Other operating expense |  |  |  |  |  |  |  |  | (78.1) | (148.5) | (85.2)
TOTAL OTHER INCOME (EXPENSE) |  |  |  |  |  |  |  |  | (294.2) | (33.8) | 161.8
Income from continuing operations before income taxes and equity loss from ventures |  |  |  |  |  |  |  |  | 129.4 | 207.0 | 313.1
Net income (loss) |  |  |  |  |  |  |  |  | 363.1 | 199.3 | (748.4)
Interest expense, net |  |  |  |  |  |  |  |  | (132.0) | (200.5) | (228.5)
Interest Income (Expense), net, including Discontinued Operations |  |  |  |  |  |  |  |  |  |  | (231.4)
Income Tax Expense (Benefit) |  |  |  |  |  |  |  |  | (252.4) | (12.2) | 169.3
Income Tax Expense (Benefit), including Discontinued Operations |  |  |  |  |  |  |  |  |  |  | (163.3)
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  | (87.7) | (115.4) | (134.0)
EBITDA |  |  |  |  |  |  |  |  | 330.4 | 503.0 | (219.7)
Gain (loss) on extinguishment/restructuring of debt |  |  |  |  |  |  |  | $ 174.3 | (165.4) | 166.3 | 392.9
LOSS FROM DISCONTINUED OPERATIONS, net of tax |  |  |  |  |  |  |  |  | (18.7) | (19.9) | (892.1)
Impairment of other long-lived assets |  |  |  |  |  |  |  |  | 0.0 | 0.0 | (3.3)
Adjusted EBITDA |  |  |  |  |  |  |  |  | 504.9 | 373.5 | 292.9
Depreciation, Depletion and Amortization excluding Depreciation, Amortization and Depletion expense for Discontinued Operations |  |  |  |  |  |  |  |  | 87.7 | 115.4 | 130.8
Capital Additions |  |  |  |  |  |  |  |  | 156.0 | 68.5 | 72.2
U.S. Iron Ore [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues from product sales and services |  |  |  |  |  |  |  |  | $ 1,866.0 | $ 1,554.5 | $ 1,525.4
Revenues from producet sales and services, percent |  |  |  |  |  |  |  |  | 80.00% | 74.00% | 76.00%
SALES MARGIN |  |  |  |  |  |  |  |  | $ 465.4 | $ 275.7 | $ 227.1
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  | (66.6) | (84.0) | (98.9)
EBITDA |  |  |  |  |  |  |  |  | 534.9 | 342.4 | 317.6
Adjusted EBITDA |  |  |  |  |  |  |  |  | 559.4 | 359.6 | 352.1
Capital Additions |  |  |  |  |  |  |  |  | 136.8 | 62.2 | 58.2
Asia Pacific Iron Ore [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues from product sales and services |  |  |  |  |  |  |  |  | $ 464.2 | $ 554.5 | $ 487.9
Revenues from producet sales and services, percent |  |  |  |  |  |  |  |  | 20.00% | 26.00% | 24.00%
SALES MARGIN |  |  |  |  |  |  |  |  | $ 36.3 | $ 113.6 | $ 9.4
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  | (14.3) | (25.1) | (25.3)
EBITDA |  |  |  |  |  |  |  |  | 40.7 | 128.3 | 35.3
Adjusted EBITDA |  |  |  |  |  |  |  |  | 50.4 | 132.9 | 32.7
Capital Additions |  |  |  |  |  |  |  |  | 2.8 | 0.2 | 5.4
All Other Segments [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  | (6.8) | (6.3) | (6.6)
Capital Additions |  |  |  |  |  |  |  |  | 16.4 | 6.1 | 8.6
Other Segment [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
EBITDA |  |  |  |  |  |  |  |  | (245.2) | 32.3 | (572.6)
Adjusted EBITDA |  |  |  |  |  |  |  |  | (104.9) | (119.0) | (91.9)
EBITDA Calculation [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  | (87.7) | (115.4) | (134.0)
Adjusted EBITDA Calculation [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Impact of Discontinued Operations |  |  |  |  |  |  |  |  |  |  | (892.0)
Foreign Exchange Remeasurement |  |  |  |  |  |  |  |  | 11.4 | (16.8) | 16.3
Severance Costs |  |  |  |  |  |  |  |  | 0.0 | (0.1) | (10.2)
Inventory Write-down |  |  |  |  |  |  |  |  | $ (1.8) | $ 0.0 | $ (16.3)

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