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INVENTORIES (Narrative) (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015
Inventory [Line Items] |  |
Cost of Goods Sold | $ 8,800,000 |
Asia Pacific Iron Ore [Member] |  |
Inventory [Line Items] |  |
Other Inventory, Noncurrent | 0 | $ 6,800,000
U.S. Iron Ore [Member] |  |
Inventory [Line Items] |  |
Inventory, LIFO Reserve | $ 78,500,000 | 87,800,000
Increase in Inventories due to build up of LIFO layers |  | $ 118,800,000

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- Definition Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(c)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Carrying amount as of the balance sheet date of inventories not expected to be converted to cash, sold or exchanged within the normal operating cycle (such as inventory related to long-term contracts or program rights). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(d)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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