Cleveland-Cliffs Inc. Annual report pursuant to Section 13 and 15(d)

Annual report pursuant to Section 13 and 15(d)

PROPERTY, PLANT AND EQUIPMENT (Value Of Each Of The Major Classes Of Consolidated Depreciable Assets) (Details)

PROPERTY, PLANT AND EQUIPMENT (Value Of Each Of The Major Classes Of Consolidated Depreciable Assets) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 2,217.7us-gaap_PropertyPlantAndEquipmentGross	$ 13,570.9us-gaap_PropertyPlantAndEquipmentGross
Accumulated Depreciation and Depletion, Property, Plant and Equipment	802.8	2,417.5
Property, plant and equipment, net	1,414.9us-gaap_PropertyPlantAndEquipmentNet	11,153.4us-gaap_PropertyPlantAndEquipmentNet	11,207.3us-gaap_PropertyPlantAndEquipmentNet
Land Rights And Mineral Rights [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	590.2	7,819.6
Office And Information Technology [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	75.5	125.7
Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	65.6	255.2
Mining Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	732.6	1,819.3
Processing Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	567.4	2,148.6
Electric Power Facilities [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	48.8	114.3
Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	25.5	69.3
Other Assets [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	60.8	227.6
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 51.3	$ 991.3