Quarterly report pursuant to Section 13 or 15(d)

SUPPLEMENTARY GUARANTOR INFORMATION (Supplementary Statements of Condensed Consolidating Operations and Comprehensive Income) (Details)

v3.8.0.1
SUPPLEMENTARY GUARANTOR INFORMATION (Supplementary Statements of Condensed Consolidating Operations and Comprehensive Income) (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Product $ 220.7 $ 412.8
Freight and venture partners' cost reimbursements 18.3 48.8
Revenues 239.0 461.6
Cost of Goods and Services Sold (242.6) (365.3)
Sales margin (3.6) 96.3
Selling, General and Administrative Expense (27.7) (27.7)
Miscellaneous - net (8.7) 11.5
Other operating expense (36.4) (16.2)
Operating Income (Loss) (40.0) 80.1
Interest expense, net (33.5) (42.8)
Loss on extinguishment of debt 0.0 (71.9)
Other non-operating income 4.4 2.5
Other expense (29.1) (112.2)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest (69.1) (32.1)
Income Tax Expense (Benefit) (15.7) 1.8
Equity in income (loss) of subsidiaries 0.0 0.0
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest (84.8) (30.3)
INCOME FROM DISCONTINUED OPERATIONS, NET OF TAX 0.5 0.5
Net Loss (84.3) (29.8)
LOSS ATTRIBUTABLE TO NONCONTROLLING INTEREST 0.0 1.7
NET LOSS ATTRIBUTABLE TO CLIFFS SHAREHOLDERS (84.3) (28.1)
Other comprehensive income (loss) 7.7 (3.0)
TOTAL COMPREHENSIVE LOSS ATTRIBUTABLE TO CLIFFS SHAREHOLDERS (76.6) (31.1)
Reportable Legal Entities [Member] | Cliffs Shareholders Equity [Member]    
Product 0.0 0.0
Freight and venture partners' cost reimbursements 0.0 0.0
Revenues 0.0 0.0
Cost of Goods and Services Sold 0.0 0.0
Sales margin 0.0 0.0
Selling, General and Administrative Expense (20.1) (19.5)
Miscellaneous - net (0.2) (0.1)
Other operating expense (20.3) (19.6)
Operating Income (Loss) (20.3) (19.6)
Interest expense, net (31.9) (41.6)
Loss on extinguishment of debt   (71.9)
Other non-operating income (0.9) (1.0)
Other expense (32.8) (114.5)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest (53.1) (134.1)
Income Tax Expense (Benefit) (15.6) 5.2
Equity in income (loss) of subsidiaries (15.7) 100.4
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest (84.4) (28.5)
INCOME FROM DISCONTINUED OPERATIONS, NET OF TAX 0.1 0.4
Net Loss   (28.1)
LOSS ATTRIBUTABLE TO NONCONTROLLING INTEREST   0.0
NET LOSS ATTRIBUTABLE TO CLIFFS SHAREHOLDERS (84.3) (28.1)
Other comprehensive income (loss) 7.7 (3.0)
TOTAL COMPREHENSIVE LOSS ATTRIBUTABLE TO CLIFFS SHAREHOLDERS (76.6) (31.1)
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]    
Product 169.2 247.3
Freight and venture partners' cost reimbursements 10.8 38.9
Revenues 180.0 286.2
Cost of Goods and Services Sold (118.5) (237.2)
Sales margin 61.5 49.0
Selling, General and Administrative Expense (4.3) (4.4)
Miscellaneous - net (5.3) (5.5)
Other operating expense (9.6) (9.9)
Operating Income (Loss) 51.9 39.1
Interest expense, net (0.8) 0.0
Loss on extinguishment of debt   0.0
Other non-operating income 0.5 (0.8)
Other expense (0.3) (0.8)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest 51.6 38.3
Income Tax Expense (Benefit) (0.1) (0.8)
Equity in income (loss) of subsidiaries 4.5 3.2
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest 56.0 40.7
INCOME FROM DISCONTINUED OPERATIONS, NET OF TAX 0.2 0.2
Net Loss   40.9
LOSS ATTRIBUTABLE TO NONCONTROLLING INTEREST   1.7
NET LOSS ATTRIBUTABLE TO CLIFFS SHAREHOLDERS 56.2 42.6
Other comprehensive income (loss) 5.9 10.8
TOTAL COMPREHENSIVE LOSS ATTRIBUTABLE TO CLIFFS SHAREHOLDERS 62.1 53.4
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]    
Product 51.5 165.5
Freight and venture partners' cost reimbursements 7.5 9.9
Revenues 59.0 175.4
Cost of Goods and Services Sold (124.1) (128.1)
Sales margin (65.1) 47.3
Selling, General and Administrative Expense (3.3) (3.8)
Miscellaneous - net (3.2) 17.1
Other operating expense (6.5) 13.3
Operating Income (Loss) (71.6) 60.6
Interest expense, net (0.8) (1.2)
Loss on extinguishment of debt   0.0
Other non-operating income 4.8 4.3
Other expense 4.0 3.1
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest (67.6) 63.7
Income Tax Expense (Benefit) 0.0 (2.6)
Equity in income (loss) of subsidiaries 0.0 0.0
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest (67.6) 61.1
INCOME FROM DISCONTINUED OPERATIONS, NET OF TAX 0.2 (0.1)
Net Loss   61.0
LOSS ATTRIBUTABLE TO NONCONTROLLING INTEREST   0.0
NET LOSS ATTRIBUTABLE TO CLIFFS SHAREHOLDERS (67.4) 61.0
Other comprehensive income (loss) 0.8 (17.8)
TOTAL COMPREHENSIVE LOSS ATTRIBUTABLE TO CLIFFS SHAREHOLDERS (66.6) 43.2
Consolidation, Eliminations [Member]    
Product 0.0 0.0
Freight and venture partners' cost reimbursements 0.0 0.0
Revenues 0.0 0.0
Cost of Goods and Services Sold 0.0 0.0
Sales margin 0.0 0.0
Selling, General and Administrative Expense 0.0 0.0
Miscellaneous - net 0.0 0.0
Other operating expense 0.0 0.0
Operating Income (Loss) 0.0 0.0
Interest expense, net 0.0 0.0
Loss on extinguishment of debt   0.0
Other non-operating income 0.0 0.0
Other expense 0.0 0.0
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest 0.0 0.0
Income Tax Expense (Benefit) 0.0 0.0
Equity in income (loss) of subsidiaries 11.2 (103.6)
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest 11.2 (103.6)
INCOME FROM DISCONTINUED OPERATIONS, NET OF TAX 0.0 0.0
Net Loss   (103.6)
LOSS ATTRIBUTABLE TO NONCONTROLLING INTEREST   0.0
NET LOSS ATTRIBUTABLE TO CLIFFS SHAREHOLDERS 11.2 (103.6)
Other comprehensive income (loss) (6.7) 7.0
TOTAL COMPREHENSIVE LOSS ATTRIBUTABLE TO CLIFFS SHAREHOLDERS $ 4.5 $ (96.6)