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 | 0us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments | 1.0us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments |
Ending Balance | 2.0us-gaap_Goodwill | 2.0us-gaap_Goodwill |
Accumulated goodwill impairment loss | (73.5)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss | (73.5)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss |
U.S. Iron Ore [Member] | ||
Goodwill [Roll Forward] | ||
Beginning Balance |
2.0us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = clf_USIronOreMember |
2.0us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = clf_USIronOreMember |
Arising in business combinations |
0us-gaap_GoodwillAcquiredDuringPeriod / us-gaap_StatementBusinessSegmentsAxis = clf_USIronOreMember |
0us-gaap_GoodwillAcquiredDuringPeriod / us-gaap_StatementBusinessSegmentsAxis = clf_USIronOreMember |
Impairment |
0us-gaap_GoodwillImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = clf_USIronOreMember |
0us-gaap_GoodwillImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = clf_USIronOreMember |
Impact of foreign currency translation |
0us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments / us-gaap_StatementBusinessSegmentsAxis = clf_USIronOreMember |
0us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments / us-gaap_StatementBusinessSegmentsAxis = clf_USIronOreMember |
Ending Balance |
2.0us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = clf_USIronOreMember |
2.0us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = clf_USIronOreMember |
Accumulated goodwill impairment loss |
0us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = clf_USIronOreMember |
0us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = clf_USIronOreMember |
Asia Pacific Iron Ore [Member] | ||
Goodwill [Roll Forward] | ||
Beginning Balance |
0us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = clf_AsiaPacificIronOreMember |
72.5us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = clf_AsiaPacificIronOreMember |
Arising in business combinations |
0us-gaap_GoodwillAcquiredDuringPeriod / us-gaap_StatementBusinessSegmentsAxis = clf_AsiaPacificIronOreMember |
0us-gaap_GoodwillAcquiredDuringPeriod / us-gaap_StatementBusinessSegmentsAxis = clf_AsiaPacificIronOreMember |
Impairment |
0us-gaap_GoodwillImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = clf_AsiaPacificIronOreMember |
(73.5)us-gaap_GoodwillImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = clf_AsiaPacificIronOreMember |
Impact of foreign currency translation |
0us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments / us-gaap_StatementBusinessSegmentsAxis = clf_AsiaPacificIronOreMember |
1.0us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments / us-gaap_StatementBusinessSegmentsAxis = clf_AsiaPacificIronOreMember |
Ending Balance |
0us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = clf_AsiaPacificIronOreMember |
0us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = clf_AsiaPacificIronOreMember |
Accumulated goodwill impairment loss |
$ (73.5)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = clf_AsiaPacificIronOreMember |
$ (73.5)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = clf_AsiaPacificIronOreMember |
X | ||||||||||
- Definition
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
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X | ||||||||||
- Definition
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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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X | ||||||||||
- Definition
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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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X | ||||||||||
- Definition
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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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X | ||||||||||
- Details
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X | ||||||||||
- Definition
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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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X | ||||||||||
- Details
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X | ||||||||||
- Details
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