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Significant Concentrations (Tables) | 12 Months Ended
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Dec. 31, 2011
Significant Concentrations [Abstract] |
Schedule Of Purchasers Accounted More Than Ten Percent Of Total Sales |
|  | September 30, |  | September 30, |  | September 30,
|  | Year Ended December 31,
|  | 2011 |  | 2010 |  | 2009
Texon L.P. |  | 18% |  | 19% |  | 30%
Plains All American Pipeline L.P. |  | 16% |  | 28% |  | N/A
Enserco Energy Inc. |  | 15% |  | N/A |  | N/A
Whiting Petroleum Corporation |  | N/A |  | 11% |  | N/A
Tesoro Refining and Marketing Company |  | N/A |  | N/A |  | 32%
N/A | Not applicable as the sales to these purchasers did not account for more than 10% of the Company's total sales for such respective periods.

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- Definition Tabular disclosure of the extent of the entity's reliance on its major customers, if revenues from transactions with a single external customer amount to 10 percent or more of entity revenues, including the disclosure of that fact, the total amount of revenues from each such customer, and the identity of the reportable segment or segments reporting the revenues. The entity need not disclose the identity of a major customer or the amount of revenues that each segment reports from that customer. For these purposes, a group of companies known to the entity to be under common control is considered a single customer, and the federal government, a state government, a local government such as a county or municipality, or a foreign government is each considered a single customer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 39 + Details
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