INVENTORIES (Schedule Of Inventories) (Details) - USD ($) $ in Millions |
Mar. 31, 2018 |
Jan. 01, 2018 |
Dec. 31, 2017 |
|---|---|---|---|
| Inventory, Net [Abstract] | Ìý | Ìý | Ìý |
| Finished Goods | $ 287.4 | Ìý | $ 160.4 |
| Work-in Process | 37.0 | Ìý | 23.0 |
| Total Inventory | 324.4 | $ 132.0 | 183.4 |
| U.S. Iron Ore [Member] | Ìý | Ìý | Ìý |
| Inventory, Net [Abstract] | Ìý | Ìý | Ìý |
| Finished Goods | 267.2 | Ìý | 127.1 |
| Work-in Process | 36.0 | Ìý | 11.3 |
| Total Inventory | 303.2 | Ìý | 138.4 |
| Asia Pacific Iron Ore [Member] | Ìý | Ìý | Ìý |
| Inventory, Net [Abstract] | Ìý | Ìý | Ìý |
| Finished Goods | 20.2 | Ìý | 33.3 |
| Work-in Process | 1.0 | Ìý | 11.7 |
| Total Inventory | $ 21.2 | Ìý | $ 45.0 |
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- Definition Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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