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Concentrations of Credit Risk (Details)	12 Months Ended
	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%

X

- Definition

The contract term of sales of gas, oil and condensate production is less than this period.

+ References

No definition available.

+ Details

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X

- Details

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X

- 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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