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Concentrations of Credit Risk (Details) | 12 Months Ended
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Jun. 30, 2012 | Jun. 30, 2011 | Jun. 30, 2010
Concentrations of Credit Risk |  |  |
Sales of gas, oil and condensate production contract term, less than | 12 years |  |
Net revenue | Major Customers | Plains Marketing L.P. |  |  |
Concentrations of Credit Risk |  |  |
Percent of Total Revenue | 84.00% | 60.00% | 12.00%
Net revenue | Major Customers | Enterprise Crude Oil LLC |  |  |
Concentrations of Credit Risk |  |  |
Percent of Total Revenue | 7.00% | 15.00% | 31.00%
Net revenue | Major Customers | ETC Texas Pipeline, LTD. |  |  |
Concentrations of Credit Risk |  |  |
Percent of Total Revenue | 3.00% | 12.00% | 19.00%
Net revenue | Major Customers | DCP Midstream, LP |  |  |
Concentrations of Credit Risk |  |  |
Percent of Total Revenue | 2.00% | 6.00% | 15.00%
Net revenue | Major Customers | Copano Field Services/Upper Gulf Coast, L.P. |  |  |
Concentrations of Credit Risk |  |  |
Percent of Total Revenue | 3.00% | 7.00% | 23.00%
Net revenue | Major Customers | Flint Hills Resources, LP |  |  |
Concentrations of Credit Risk |  |  |
Percent of Total Revenue | 1.00% |  |

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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13537-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13531-108611 + Details
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