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INVENTORIES (Narrative) (Details) - USD ($) $ in Millions | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | ---
Asia Pacific Iron Ore [Member] |  |
Inventory [Line Items] |  |
Other Inventory, Noncurrent | $ 6.8 | $ 0.0
U.S. Iron Ore [Member] |  |
Inventory [Line Items] |  |
Inventory, LIFO Reserve | 87.8 | 119.0
Increase in Inventories due to build up of LIFO layers | $ 118.8 | $ 44.8

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- Definition Amount of difference between inventory at lower of LIFO cost or market and inventory at lower of other inventory accounting method cost or market, for example, but not limited to, FIFO or average cost. + 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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