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

PENSIONS AND OTHER POSTRETIREMENT BENEFITS (Weighted-Average Assumptions Used to Determine Benefit Obligations) (Details)	Dec. 31, 2013	Dec. 31, 2012
Pension Benefits [Member] \| United States [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	4.57%	3.70%
Expected return on plan assets	8.25%	8.25%
Pension Benefits [Member] \| Canada [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	4.50%	3.75%
Expected return on plan assets	7.25%	7.25%
Other Benefits [Member] \| United States [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	4.57%	3.70%
Expected return on plan assets	7.00%	8.25%
Other Benefits [Member] \| Canada [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	4.75%	4.00%
Salary [Member] \| Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Rate of compensation increase	4.00%	4.00%
Hourly [Member] \| Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Rate of compensation increase	3.00%	4.00%