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SEGMENT REPORTING SEGMENT REPORTING (Revenue from External Customers by Products and Services) (Details) - Sales Revenue, Net [Member] - Product Concentration Risk [Member] | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Revenue from External Customer [Line Items] |  |  |
Concentration Risk, Percentage | 100.00% | 100.00% | 100.00%
Iron Ore Revenue [Member] |  |  |
Revenue from External Customer [Line Items] |  |  |
Concentration Risk, Percentage | 91.00% | 92.00% | 93.00%
Freight and Venture Partners' Cost Reimbursements [Member] |  |  |
Revenue from External Customer [Line Items] |  |  |
Concentration Risk, Percentage | 9.00% | 8.00% | 7.00%

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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13531-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6404-108592 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13537-108611 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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