PROPERTY, PLANT AND EQUIPMENT (Value Of Each Of The Major Classes Of Consolidated Depreciable Assets) (Details) (USD $)
In Millions, unless otherwise specified |
Mar. 31, 2015
|
Dec. 31, 2014
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Property, Plant and Equipment [Line Items] | Ìý | Ìý |
Property, plant and equipment, gross | $ 1,872.0us-gaap_PropertyPlantAndEquipmentGross | $ 1,870.2us-gaap_PropertyPlantAndEquipmentGross |
Accumulated Depreciation and Depletion, Property, Plant and Equipment | (824.8)clf_AccumulatedDepreciationandDepletionPropertyPlantandEquipment | (799.7)clf_AccumulatedDepreciationandDepletionPropertyPlantandEquipment |
Property, plant and equipment, net | 1,047.2us-gaap_PropertyPlantAndEquipmentNet | 1,070.5us-gaap_PropertyPlantAndEquipmentNet |
Land Rights And Mineral Rights [Member] | Ìý | Ìý |
Property, Plant and Equipment [Line Items] | Ìý | Ìý |
Property, plant and equipment, gross |
500.5us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_MiningPropertiesAndMineralRightsMember |
500.5us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_MiningPropertiesAndMineralRightsMember |
Office And Information Technology [Member] | Ìý | Ìý |
Property, Plant and Equipment [Line Items] | Ìý | Ìý |
Property, plant and equipment, gross |
69.7us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ComputerEquipmentMember |
73.7us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ComputerEquipmentMember |
Buildings [Member] | Ìý | Ìý |
Property, Plant and Equipment [Line Items] | Ìý | Ìý |
Property, plant and equipment, gross |
59.8us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_BuildingMember |
59.8us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_BuildingMember |
Mining Equipment [Member] | Ìý | Ìý |
Property, Plant and Equipment [Line Items] | Ìý | Ìý |
Property, plant and equipment, gross |
584.9us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_EquipmentMember |
585.1us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_EquipmentMember |
Processing Equipment [Member] | Ìý | Ìý |
Property, Plant and Equipment [Line Items] | Ìý | Ìý |
Property, plant and equipment, gross |
512.7us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_OtherMachineryAndEquipmentMember |
510.2us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_OtherMachineryAndEquipmentMember |
Electric Power Facilities [Member] | Ìý | Ìý |
Property, Plant and Equipment [Line Items] | Ìý | Ìý |
Property, plant and equipment, gross |
44.2us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricGenerationEquipmentMember |
46.8us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricGenerationEquipmentMember |
Land Improvements [Member] | Ìý | Ìý |
Property, Plant and Equipment [Line Items] | Ìý | Ìý |
Property, plant and equipment, gross |
24.8us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_LandImprovementsMember |
24.7us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_LandImprovementsMember |
Other [Member] | Ìý | Ìý |
Property, Plant and Equipment [Line Items] | Ìý | Ìý |
Property, plant and equipment, gross |
54.7us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_OtherAssetsMember |
55.0us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_OtherAssetsMember |
Construction in Progress [Member] | Ìý | Ìý |
Property, Plant and Equipment [Line Items] | Ìý | Ìý |
Property, plant and equipment, gross |
$ 20.7us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ConstructionInProgressMember |
$ 14.4us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ConstructionInProgressMember |
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Amount of accumulated depreciation and depletion for physical assets used in the normal conduct of business to produce goods and services. No definition available.
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- Definition
Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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