Annual report pursuant to Section 13 and 15(d)

Earnings Per Share (Earnings Per Share Computation) (Details)

v2.4.0.6
Earnings Per Share (Earnings Per Share Computation) (Details) (USD $)
In Millions, except Share data, unless otherwise specified
3 Months Ended 12 Months Ended
Dec. 31, 2011
Sep. 30, 2011
Jun. 30, 2011
Mar. 31, 2011
Dec. 31, 2010
Sep. 30, 2010
Jun. 30, 2010
Mar. 31, 2010
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Earnings Per Share [Abstract]                      
Net income from continuing operations attributable to Cliffs shareholders $ 185.3 $ 618.7 $ 409.8 $ 423.8 $ 385.2 $ 298.3 $ 261.5 $ 78.0 $ 1,637.6 $ 1,023.0 $ 208.5
Loss from discontinued operations 0.1 (17.5) (0.7) (0.4) (1.1) (0.7) (0.7) (0.6) (18.5) (3.1) (3.4)
Net Income Attributable to Cliffs Shareholders $ 185.4 $ 601.2 $ 409.1 $ 423.4 $ 384.1 $ 297.6 $ 260.8 $ 77.4 $ 1,619.1 $ 1,019.9 $ 205.1
Number of Shares:                      
Basic                 140,234,000 135,301,000 124,998,000
Employee stock plans                 800,000 800,000 800,000
Diluted                 141,012,000 136,138,000 125,751,000
Income (Loss) from Continuing Operations, Per Basic Share $ 1.30 $ 4.29 $ 2.95 $ 3.12 $ 2.85 $ 2.20 $ 1.93 $ 0.58 $ 11.68 $ 7.56 $ 1.67
Income (Loss) from Discontinued Operations, Net of Tax, Per Basic Share   $ (0.12) $ (0.01)   $ (0.01) $ (0.01)     $ (0.13) $ (0.02) $ (0.03)
EARNINGS PER COMMON SHARE ATTRIBUTABLE TO CLIFFS SHAREHOLDERS - BASIC $ 1.30 $ 4.17 $ 2.94 $ 3.12 $ 2.84 $ 2.19 $ 1.93 $ 0.58 $ 11.55 $ 7.54 $ 1.64
Income (Loss) from Continuing Operations, Per Diluted Share $ 1.30 $ 4.27 $ 2.93 $ 3.11 $ 2.83 $ 2.19 $ 1.92 $ 0.57 $ 11.61 $ 7.51 $ 1.66
Income (Loss) from Discontinued Operations, Net of Tax, Per Diluted Share   $ (0.12) $ (0.01)   $ (0.01) $ (0.01)     $ (0.13) $ (0.02) $ (0.03)
EARNINGS PER COMMON SHARE ATTRIBUTABLE TO CLIFFS SHAREHOLDERS - DILUTED $ 1.30 $ 4.15 $ 2.92 $ 3.11 $ 2.82 $ 2.18 $ 1.92 $ 0.57 $ 11.48 $ 7.49 $ 1.63