Segment Reporting (Schedule Of Segment Reporting Information, By Segment) (Details) (USD $) In Millions, unless otherwise specified |
3 Months Ended | 9 Months Ended | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Sep. 30, 2011 |
Sep. 30, 2010 |
Sep. 30, 2011 |
Sep. 30, 2010 |
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| Percentage of revenues from product sales and services | 100.00% | 100.00% | 100.00% | 100.00% | ||||||
| Revenues from product sales and services | $ 2,142.8 | $ 1,346.0 | $ 5,131.8 | $ 3,257.9 | ||||||
| Sales margin | 863.3 | 477.2 | 2,194.9 | 1,042.6 | ||||||
| Other operating expense | (43.0) | (86.8) | (214.2) | (170.9) | ||||||
| Other income (expense) | (54.8) | 20.2 | (61.8) | 39.8 | ||||||
| INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND EQUITY INCOME FROM VENTURES | 765.5 | 410.6 | 1,918.9 | 911.5 | ||||||
| Depreciation, depletion and amortization | 117.7 | 84.4 | 302.9 | 239.5 | ||||||
| Capital additions | 255.9 | [1] | 83.5 | [1] | 553.3 | [1] | 154.2 | [1] | ||
U.S. Iron Ore [Member] |
Ìý | Ìý | Ìý | Ìý | ||||||
| Percentage of revenues from product sales and services | 52.00% | 55.00% | 49.00% | 53.00% | ||||||
| Revenues from product sales and services | 1,106.7 | 741.4 | 2,502.0 | 1,729.8 | ||||||
| Sales margin | 481.3 | 264.2 | 1,283.7 | 545.5 | ||||||
| Depreciation, depletion and amortization | 23.0 | 17.6 | 62.5 | 45.1 | ||||||
| Capital additions | 28.5 | [1] | 32.7 | [1] | 115.8 | [1] | 59.9 | [1] | ||
Eastern Canadian Iron Ore [Member] |
Ìý | Ìý | Ìý | Ìý | ||||||
| Percentage of revenues from product sales and services | 24.00% | 9.00% | 18.00% | 9.00% | ||||||
| Revenues from product sales and services | 517.3 | 124.4 | 942.2 | 308.1 | ||||||
| Sales margin | 193.0 | 39.6 | 296.0 | 76.3 | ||||||
| Depreciation, depletion and amortization | 41.2 | 10.6 | 81.1 | 36.2 | ||||||
| Capital additions | 103.3 | [1] | 4.8 | [1] | 167.5 | [1] | 9.4 | [1] | ||
North American Coal [Member] |
Ìý | Ìý | Ìý | Ìý | ||||||
| Percentage of revenues from product sales and services | 3.00% | 9.00% | 8.00% | 10.00% | ||||||
| Revenues from product sales and services | 64.0 | 126.1 | 388.7 | 323.4 | ||||||
| Sales margin | (42.7) | (17.8) | (60.4) | (5.4) | ||||||
| Depreciation, depletion and amortization | 19.7 | 19.6 | 62.1 | 42.6 | ||||||
| Capital additions | 60.3 | [1] | 28.1 | [1] | 116.3 | [1] | 42.0 | [1] | ||
Asia Pacific Iron Ore [Member] |
Ìý | Ìý | Ìý | Ìý | ||||||
| Percentage of revenues from product sales and services | 19.00% | 22.00% | 22.00% | 24.00% | ||||||
| Revenues from product sales and services | 400.1 | 298.2 | 1,127.1 | 767.1 | ||||||
| Sales margin | 214.6 | 169.7 | 615.4 | 382.5 | ||||||
| Depreciation, depletion and amortization | 25.4 | 31.0 | 74.3 | 97.2 | ||||||
| Capital additions | 57.3 | [1] | 10.4 | [1] | 140.6 | [1] | 30.6 | [1] | ||
Other Segment [Member] |
Ìý | Ìý | Ìý | Ìý | ||||||
| Percentage of revenues from product sales and services | 2.00% | 5.00% | 3.00% | 4.00% | ||||||
| Revenues from product sales and services | 54.7 | 55.9 | 171.8 | 129.5 | ||||||
| Sales margin | 17.1 | 21.5 | 60.2 | 43.7 | ||||||
| Depreciation, depletion and amortization | 8.4 | 5.6 | 22.9 | 18.4 | ||||||
| Capital additions | $ 6.5 | [1] | $ 7.5 | [1] | $ 13.1 | [1] | $ 12.3 | [1] | ||
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- Definition Percentage of Segment Revenue
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- Definition Total expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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