Quarterly report pursuant to Section 13 or 15(d)

SEGMENT REPORTING SEGMENT REPORTING (Schedule of Segment Reporting Information) (Details)

v3.10.0.1
SEGMENT REPORTING SEGMENT REPORTING (Schedule of Segment Reporting Information) (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Segment Reporting Information [Line Items]        
Amortization of Intangible Assets $ 0.2 $ 0.2 $ 0.4 $ 0.4
NET INCOME 165.1 30.1 80.8 0.3
Revenues 714.3 471.3 894.3 757.5
Gross Profit 284.5 144.7 346.0 193.7
Other operating expense (30.3) (29.5) (61.5) (45.1)
Nonoperating Income (Expense) (26.6) (32.5) (54.6) (143.3)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest 227.6 82.7 229.9 5.3
Interest expense, net (31.2) (30.1) (63.6) (71.5)
Income Tax Expense (Benefit) (1.8) (1.1) 13.9 0.0
Depreciation, depletion and amortization     (49.4) (44.8)
EBITDA 221.1 85.7 209.9 120.1
LOSS FROM DISCONTINUED OPERATIONS, NET OF TAX (64.3) (53.7) (135.2) (5.0)
Foreign currency transaction gain (loss), before tax (0.1) 0.5 (0.5) 15.3
Gain (loss) on extinguishment of debt 0.2 (4.9) 0.2 (76.8)
Adjusted EBITDA 275.7 135.5 328.0 175.1
Property, Plant and Equipment, Additions 70.4 24.6 149.3 51.7
Payments To Acquire Property Plant And Equipment Net     (114.4) (48.5)
Payments to Acquire Property, Plant, and Equipment     72.3 5.1
Capital Expenditures Incurred but Not yet Paid     34.9 3.2
U.S. Iron Ore [Member]        
Segment Reporting Information [Line Items]        
Revenues $ 714.3 $ 471.3 $ 894.3 $ 757.5
Percentage Of Segment Revenue 100.00% 100.00% 100.00% 100.00%
Gross Profit $ 284.5 $ 144.7 $ 346.0 $ 193.7
Depreciation, depletion and amortization (15.6) (16.7) (31.4) (33.1)
EBITDA 296.0 155.0 368.5 212.9
Adjusted EBITDA 301.3 161.5 378.4 225.6
Property, Plant and Equipment, Additions 26.7 24.6 45.4 51.7
All Segments        
Segment Reporting Information [Line Items]        
Depreciation, depletion and amortization (17.0) (18.3) (34.2) (36.8)
EBITDA (74.9) (69.3) (158.6) (92.8)
Adjusted EBITDA (25.6) (26.0) (50.4) (50.5)
Corporate and Other [Member]        
Segment Reporting Information [Line Items]        
Depreciation, depletion and amortization (1.4) (1.6) (2.8) (3.7)
Property, Plant and Equipment, Additions 43.7 0.0 103.9 0.0
EBITDA Calculation [Member]        
Segment Reporting Information [Line Items]        
Interest expense, net (32.3) (31.4) (65.8) (74.2)
Income Tax Expense (Benefit) 1.8 (2.6) (13.9) (0.8)
Depreciation, depletion and amortization (25.5) (21.6) (49.4) (44.8)
Adjusted EBITDA Calculation [Member]        
Segment Reporting Information [Line Items]        
LOSS FROM DISCONTINUED OPERATIONS, NET OF TAX $ (54.7) $ (45.4) $ (117.8) $ 6.5