BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Investments In Unconsolidated Ventures) (Details) - Related Party [Domain] - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Investment	$ 2.0	$ 4.1
Other Noncurrent Liabilities [Member] \| Hibbing [Member]
Schedule of Equity Method Investments [Line Items]
Investment		3.1
Other Noncurrent Assets [Member] \| Hibbing [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest, equity method investment	23.00%
Investment	$ 0.9
Other Noncurrent Assets [Member] \| Other Equity Investees [Member]
Schedule of Equity Method Investments [Line Items]
Investment	$ 1.1	$ 1.0

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35755396&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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+ References

No definition available.

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