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Major Lessees | 12 Months Ended
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Dec. 31, 2011
Major Lessees [Abstract] |
Major Lessees | 14. Major Lessees The Partnership has the following lessees that generated in excess of ten percent of total revenues in any one of the years ended December 31, 2011, 2010, and 2009. Revenues from these lessees are as follows:
|  | For the Years Ended December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
|  | Revenues |  |  | Percent |  |  | Revenues |  |  | Percent |  |  | Revenues |  |  | Percent |
|  | (Dollars in thousands) |
Alpha Natural Resources |  | $ | 107,267 |  |  |  | 28.4 | % |  | $ | 79,084 |  |  |  | 26.2 | % |  | $ | 64,626 |  |  |  | 25.2 | %
The Cline Group |  | $ | 64,829 |  |  |  | 17.2 | % |  | $ | 62,372 |  |  |  | 20.7 | % |  | $ | 37,369 |  |  |  | 14.6 | %
In 2011, the Partnership derived over 46% of its revenue from two companies listed above. As a result, the Partnership has a significant concentration of revenues with those lessees, although in most cases, with the exception of the Williamson mine operated by an affiliate of the Cline group, the exposure is spread out over a number of different mining operations and leases. Cline’s Williamson mine alone was responsible for approximately 12% of our total revenues for 2011. As a result of the merger of Alpha Natural Resources and Massey Energy Company, all prior period revenues from Massey have been combined with those of Alpha for presentation purposes in this 10-K. Substantially all of the Partnership’s accounts receivable result from amounts due from third-party companies in the coal industry, with approximately 61% of our total revenues being attributable to coal royalty revenues from Appalachia. This concentration of customers may impact the Partnership’s overall credit risk, either positively or negatively, in that these entities may be affected by changes in economic or other conditions. Receivables are generally not collateralized.

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- Definition Disclosure of lessee(s) that make up greater than 10% of our total revenue. + References No definition available. + Details
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