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Concentrations of Credit Risk - Schedule of Credit Risk (Details) - Net revenue - Major Customers	12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Concentrations of Credit Risk
Percent of Total Revenue	100.00%	100.00%	100.00%
Plains Marketing L.P. (includes Delhi production)
Concentrations of Credit Risk
Percent of Total Revenue	99.00%	99.00%	96.00%
Enterprise Crude Oil LLC
Concentrations of Credit Risk
Percent of Total Revenue	0.00%	0.00%	2.00%
Flint Hills
Concentrations of Credit Risk
Percent of Total Revenue	0.00%	0.00%	1.00%
ETC Texas Pipeline, LTD.
Concentrations of Credit Risk
Percent of Total Revenue	0.00%	0.00%	1.00%
All others
Concentrations of Credit Risk
Percent of Total Revenue	1.00%	1.00%	0.00%

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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=64851502&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 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

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-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
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-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

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