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Earnings before Interest, Taxes, and Depreciation, Depletion and Amortization

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Foreign Exchange Remeasurement

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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.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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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, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenues from product sales and services	$ 696.3	$ 741.8	$ 714.3	$ 180.0	$ 511.8	$ 596.7	$ 471.3	$ 286.2	$ 2,332.4	$ 1,866.0	$ 1,554.5
SALES MARGIN	$ 202.0	$ 261.6	$ 284.5	$ 61.5	$ 116.1	$ 157.8	$ 144.7	$ 49.0	809.6	467.6	280.1
Other operating expense									136.4	77.4	149.4
TOTAL OTHER INCOME (EXPENSE)									(108.5)	(282.0)	(20.3)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES									564.7	108.2	110.4
Net income									1,128.1	363.1	199.3
Depreciation, depletion and amortization									(89.0)	(87.7)	(115.4)
EBITDA									878.1	330.4	503.0
Gain (loss) on extinguishment/restructuring of debt									(6.8)	(165.4)	166.3
Adjusted EBITDA									766.3	459.9	246.1
Depreciation, Depletion and Amortization excluding Depreciation, Amortization and Depletion expense for Discontinued Operations									73.8	73.4	90.3
Capital Additions									394.7	153.2	68.3
Mining and Pelletizing [Member]
Segment Reporting Information [Line Items]
Revenues from product sales and services									2,332.4	1,866.0	1,554.5
SALES MARGIN									809.6	467.6	280.1
Depreciation, depletion and amortization									(68.2)	(66.6)	(84.0)
EBITDA									852.9	534.9	342.4
Adjusted EBITDA									875.3	559.4	359.6
Capital Additions									145.0	136.8	62.2
Metallics [Member]
Segment Reporting Information [Line Items]
EBITDA									(3.3)	(0.4)	0.0
Adjusted EBITDA									(3.3)	(0.4)	0.0
Capital Additions									248.1	13.7	0.0
All Other Segments [Member]
Segment Reporting Information [Line Items]
Depreciation, depletion and amortization									(5.6)	(6.8)	(6.3)
Capital Additions									1.6	2.7	6.1
Other Segment [Member]
Segment Reporting Information [Line Items]
EBITDA									28.5	(204.1)	160.6
Adjusted EBITDA									(105.7)	(99.1)	(113.5)
EBITDA Calculation [Member]
Segment Reporting Information [Line Items]
Interest Income (Expense), net, including Discontinued Operations									(121.3)	(132.0)	(200.5)
Income Tax Expense (Benefit), including Discontinued Operations									460.3	252.4	12.2
Depreciation, depletion and amortization									(89.0)	(87.7)	(115.4)
Adjusted EBITDA Calculation [Member]
Segment Reporting Information [Line Items]
Impact of Discontinued Operations									120.6	22.0	108.4
Foreign Exchange Remeasurement									(0.9)	13.9	(17.8)
Impairment of other long-lived assets									$ (1.1)	$ 0.0	$ 0.0