BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Investments In Unconsolidated Ventures) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014		Dec. 31, 2013
Schedule of Equity Method Investments [Line Items]
Investment	$ 32.5		$ 30.8
Other Noncurrent Liabilities [Member] | Hibbing [Member]
Schedule of Equity Method Investments [Line Items]
Investment			(3.9)	[1]
Other Noncurrent Assets [Member] | Hibbing [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest, equity method investment	23.00%	[1]
Investment	8.1	[1]
Other Noncurrent Assets [Member] | Other Equity Investees [Member]
Schedule of Equity Method Investments [Line Items]
Investment	$ 24.4		$ 34.7

[1] At December 31, 2013, the classification for Hibbing was Other liabilities.