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Coal and Other Mineral Rights | 12 Months Ended
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Dec. 31, 2011
Coal and Other Mineral Rights [Abstract] |
Coal and Other Mineral Rights | 7. Coal and Other Mineral Rights The Partnership’s coal and other mineral rights consist of the following:
|  | December 31, 2011 |  |  | December 31, 2010 |
|  | (In thousands) |
Coal and other mineral rights |  | $ | 1,645,451 |  |  | $ | 1,629,286 |
Less accumulated depletion and amortization |  |  | (387,950 | ) |  |  | (347,650 | )
Net book value |  | $ | 1,257,501 |  |  | $ | 1,281,636 |
|  | For the years ended December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
|  | (In thousands) |
Total depletion and amortization expense on coal and other mineral interests |  | $ | 47,230 |  |  | $ | 38,501 |  |  | $ | 48,591 |
Included in depletion in 2009 is a charge of $8.2 million related to a terminated lease from a mine closure.

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- Definition Disclosure of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. Examples include coal mineral, aggregate mineral, oil and gas mineral and land. + References No definition available. + Details
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