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

Annual report pursuant to Section 13 and 15(d)

SEGMENT REPORTING SEGMENTS REPORTING (Revenue by Geographical Location) (Details)

SEGMENT REPORTING SEGMENTS REPORTING (Revenue by Geographical Location) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 1,284.7us-gaap_Revenues	$ 1,298.2us-gaap_Revenues	$ 1,100.8us-gaap_Revenues	$ 940.0us-gaap_Revenues	$ 1,515.8us-gaap_Revenues	$ 1,546.6us-gaap_Revenues	$ 1,488.5us-gaap_Revenues	$ 1,140.5us-gaap_Revenues	$ 4,623.7us-gaap_Revenues	$ 5,691.4us-gaap_Revenues	$ 5,872.7us-gaap_Revenues
PROPERTY, PLANT AND EQUIPMENT, NET	1,414.9us-gaap_PropertyPlantAndEquipmentNet				11,153.4us-gaap_PropertyPlantAndEquipmentNet				1,414.9us-gaap_PropertyPlantAndEquipmentNet	11,153.4us-gaap_PropertyPlantAndEquipmentNet	11,207.3us-gaap_PropertyPlantAndEquipmentNet
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									2,139.4	1,857.6	2,108.5
PROPERTY, PLANT AND EQUIPMENT, NET	1,093.7				2,721.6				1,093.7	2,721.6	2,795.3
AUSTRALIA
Revenues from External Customers and Long-Lived Assets [Line Items]
PROPERTY, PLANT AND EQUIPMENT, NET	72.4				751.0				72.4	751.0	1,042.4
China [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									1,049.0	1,909.4	2,008.2
Canada [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									439.1	871.2	728.1
PROPERTY, PLANT AND EQUIPMENT, NET	248.8				7,680.8				248.8	7,680.8	7,369.6
Other Countries [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									$ 996.2	$ 1,053.2	$ 1,027.9