GOODWILL AND OTHER INTANGIBLE ASSETS AND LIABILITIES (Schedule Of Goodwill) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Goodwill [Roll Forward]
Beginning Balance	$ 2.0us-gaap_Goodwill	$ 74.5us-gaap_Goodwill
Arising in business combinations	0us-gaap_GoodwillAcquiredDuringPeriod	0us-gaap_GoodwillAcquiredDuringPeriod
Impairment	0us-gaap_GoodwillImpairmentLoss	(73.5)us-gaap_GoodwillImpairmentLoss
Impact of foreign currency translation	0	1.0
Ending Balance	2.0us-gaap_Goodwill	2.0us-gaap_Goodwill
Accumulated goodwill impairment loss	(73.5)	(73.5)
U.S. Iron Ore [Member]
Goodwill [Roll Forward]
Beginning Balance	2.0	2.0
Arising in business combinations	0	0
Impairment	0	0
Impact of foreign currency translation	0	0
Ending Balance	2.0	2.0
Accumulated goodwill impairment loss	0	0
Asia Pacific Iron Ore [Member]
Goodwill [Roll Forward]
Beginning Balance	0	72.5
Arising in business combinations	0	0
Impairment	0	(73.5)
Impact of foreign currency translation	0	1.0
Ending Balance	0	0
Accumulated goodwill impairment loss	$ (73.5)	$ (73.5)

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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