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Business Summary And Significant Accounting Policies (Book Value Of Land And Mineral Rights Disclosure) (Details) (USD $)
In Millions, unless otherwise specified |
Dec. 31, 2011
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Dec. 31, 2010
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| Business Summary And Significant Accounting Policies [Abstract] | ||
| Land rights | $ 37.3 | $ 36.8 |
| Mineral rights: | ||
| Cost | 7,881.6 | 2,983.1 |
| Less depletion | 533.9 | 376.4 |
| Net mineral rights | $ 7,347.7 | $ 2,606.7 |
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- Definition
Period end amount of property, plant and equipment (PPE) related to land rights. No definition available.
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- Details
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- Definition
The accumulated decrease in the carrying value of the mineral properties as a result of mine or mineral production. No definition available.
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- Definition
Carrying amount at the balance sheet date of mineral properties, gross of adjustments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Mineral properties, net of adjustments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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