Annual report pursuant to Section 13 and 15(d)

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Depreciation Methods and Useful Lives) (Details)

v2.4.0.8
BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Depreciation Methods and Useful Lives) (Details)
12 Months Ended
Dec. 31, 2013
U.S. Iron Ore and Eastern Canadian Iron Ore [Member] | Computer Equipment [Member] | Minimum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 2 years
U.S. Iron Ore and Eastern Canadian Iron Ore [Member] | Computer Equipment [Member] | Maximum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 7 years
U.S. Iron Ore and Eastern Canadian Iron Ore [Member] | Equipment [Member] | Minimum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 10 years
U.S. Iron Ore and Eastern Canadian Iron Ore [Member] | Equipment [Member] | Maximum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 20 years
U.S. Iron Ore and Eastern Canadian Iron Ore [Member] | Building [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 45 years
U.S. Iron Ore and Eastern Canadian Iron Ore [Member] | Other Machinery and Equipment [Member] | Minimum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 15 years
U.S. Iron Ore and Eastern Canadian Iron Ore [Member] | Other Machinery and Equipment [Member] | Maximum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 45 years
Asia Pacific Iron Ore [Member] | Property, Plant and Equipment [Member] | Minimum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 5 years
Asia Pacific Iron Ore [Member] | Property, Plant and Equipment [Member] | Maximum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 10 years
Asia Pacific Iron Ore [Member] | Mine Development [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 6 years
Asia Pacific Iron Ore [Member] | Vehicles And Office Equipment [Member] | Minimum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 3 years
Asia Pacific Iron Ore [Member] | Vehicles And Office Equipment [Member] | Maximum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 5 years
North American Coal [Member] | Computer Equipment [Member] | Minimum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 2 years
North American Coal [Member] | Computer Equipment [Member] | Maximum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 3 years
North American Coal [Member] | Equipment [Member] | Minimum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 2 years
North American Coal [Member] | Equipment [Member] | Maximum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 22 years
North American Coal [Member] | Building [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 30 years
North American Coal [Member] | Other Machinery and Equipment [Member] | Minimum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 2 years
North American Coal [Member] | Other Machinery and Equipment [Member] | Maximum [Member]
 
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 30 years