Acquisitions And Other Investments (Consolidated Thompson Pro Forma Information) (Details) (Consolidated Thompson [Member], USD $) In Millions, except Per Share data |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2011 |
Sep. 30, 2010 |
Sep. 30, 2011 |
Sep. 30, 2010 |
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Consolidated Thompson [Member] |
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| Revenues from product sales and services | $ 2,142.8 | $ 1,487.5 | $ 5,340.2 | $ 3,435.2 |
| Net income attributable to Cliffs shareholders | $ 595.6 | $ 315.2 | $ 1,426.2 | $ 515.5 |
| Earnings per common share attributable to Cliffs shareholders - Basic | $ 4.13 | $ 2.33 | $ 10.22 | $ 3.81 |
| Earnings per common share attributable to Cliffs shareholders - Diluted | $ 4.11 | $ 2.31 | $ 10.16 | $ 3.79 |
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- Definition The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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