Quarterly report pursuant to Section 13 or 15(d)

Shareholders' Equity (Schedule Of Stockholders' Equity) (Details)

v2.4.0.6
Shareholders' Equity (Schedule Of Stockholders' Equity) (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2012
Mar. 31, 2011
Beginning Balance, December 31 $ 7,039.7 $ 3,838.7
Net income 391.4 423.4
Net Income Attributable to Cliffs Shareholders 375.8 423.4
Net income including operations   423.3
Other comprehensive income 23.2 24.6
Total comprehensive income 414.6 447.9
Purchase of additional noncontrolling interest   (0.1)
Stock and other incentive plans (2.8) (1.3)
Common stock dividends (39.7) (19.0)
Purchase of subsidiary shares from noncontrolling interest   7.5
Undistributed gains to noncontrolling interest 7.8 0.2
Capital contribution by noncontrolling interest to subsidiary 22.3  
Acquisition of controlling interest (8.0)  
Ending Balance, March 31 7,433.9 4,273.9
Non- Controlling Interest [Member]
   
Beginning Balance, December 31 1,254.7 (7.2)
Net income 15.6  
Net income including operations   (0.1)
Other comprehensive income 1.5 0.5
Total comprehensive income 17.1 0.4
Purchase of subsidiary shares from noncontrolling interest   7.5
Undistributed gains to noncontrolling interest 7.8 0.2
Capital contribution by noncontrolling interest to subsidiary 22.3  
Acquisition of controlling interest (8.0)  
Ending Balance, March 31 1,293.9 0.9
Cliffs Shareholders' Equity [Member]
   
Beginning Balance, December 31 5,785.0 3,845.9
Net Income Attributable to Cliffs Shareholders 375.8  
Net income including operations   423.4
Other comprehensive income 21.7 24.1
Total comprehensive income 397.5 447.5
Purchase of additional noncontrolling interest   (0.1)
Stock and other incentive plans (2.8) (1.3)
Common stock dividends (39.7) (19.0)
Ending Balance, March 31 $ 6,140.0 $ 4,273.0
Empire [Member]
   
Percentage Of Ownership Interests 79.00% 79.00%
Tilden [Member]
   
Percentage Of Ownership Interests 85.00% 85.00%
Bloom Lake [Member]
   
Percentage Of Ownership Interests 75.00% 75.00%