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Dehli Field Litigation Settlement (Details) - USD ($)			12 Months Ended
	Jul. 01, 2016	Jun. 24, 2016	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Loss Contingencies [Line Items]
Delhi field litigation settlement gain			$ 28,096,500	$ 0	$ 0
Fair value of litigation settlement			596,500	$ 0	$ 0
Dehli Field Litigation
Loss Contingencies [Line Items]
Delhi field litigation settlement gain			$ 28,100,000
Dehli Field Litigation | Denbury Resources, Inc
Loss Contingencies [Line Items]
Delhi field litigation settlement gain		$ 28,100,000
Proceeds from litigation		$ 27,500,000
Working interest in Mengal Sand Interval		23.90%
Fair value of litigation settlement		$ 596,500
Dehli Field Litigation | Denbury Resources, Inc | Subsequent Event
Loss Contingencies [Line Items]
Overriding royalty interest in Holt-Bryant	0.2226%
Dehli Field Litigation | Denbury Resources, Inc | Level 2
Loss Contingencies [Line Items]
Fair value of litigation settlement		$ 596,500

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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Cash received for the settlement of litigation during the current period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

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