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Self Insurance | 12 Months Ended
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Dec. 31, 2014
Self Insurance [Abstract] |
Self Insurance | (8) Self Insurance In late August 2010 we decided to terminate the property insurance on our underground mining equipment. Such equipment is allocated among 11 mining units at our three underground mines. These units are spread out over 30 miles in 11 different locations at the three mines. The historical cost of such equipment is about $246 million.

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