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Significant Concentrations | 12 Months Ended
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Dec. 31, 2011
Significant Concentrations [Abstract] |
Significant Concentrations | 13. Significant Concentrations Purchasers that accounted for more than 10% of the Company's total sales for the periods presented are as follows:
|  | 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.
No other purchasers accounted for more than 10% of the Company's total oil and natural gas sales for the years ended December 31, 2011, 2010 and 2009. Management believes that the loss of any of these purchasers would not have a material adverse effect on the Company's operations, as there are a number of alternative oil and natural gas purchasers in the Company's producing regions. Substantially all of the Company's accounts receivable result from sales of oil and natural gas as well as joint interest billings ("JIB") to third-party companies who have working interest payment obligations in projects completed by the Company. Northern Oil & Gas Inc. and Hess Corporation accounted for approximately 16% and 14%, respectively, of the Company's JIB receivables balance at December 31, 2011. Brigham Oil & Gas LP and Hess Corporation accounted for approximately 44% and 12%, respectively, of the Company's JIB receivables balance at December 31, 2010. This concentration of customers and joint interest owners may impact the Company's overall credit risk, either positively or negatively, in that these entities may be similarly affected by changes in economic or other conditions.

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- Definition The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8595-108599 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8538-108599 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8971-108599 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8981-108599 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 29 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8864-108599 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8380-108599 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 35 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8984-108599 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 41 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9038-108599 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8933-108599 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 11: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 30 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8906-108599 Reference 12: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 26 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8844-108599 Reference 13: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 40 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9031-108599 Reference 14: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 42 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9054-108599 Reference 15: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 31 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8924-108599 + Details
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