Organization and Basis of Presentation - Additional Information (Details)		12 Months Ended
Dec. 19, 2014 Subsidiary shares	Dec. 31, 2015 shares
Oak Valley Resources, LLC [Member]
Organization And Basis Of Presentation [Line Items]
Number of subsidiaries \| Subsidiary	3
Common stock shares issued in exchange for acquisition	9,124,000
Percentage of common stock acquired	84.00%	66.00%
Flatonia Energy, LLC [Member]
Organization And Basis Of Presentation [Line Items]
Percentage of common stock acquired		20.00%
Additional ownership interest acquired in certain oil and gas properties		20.00%
Common stock shares issued in exchange for acquisition		2,957,000
Undivided ownership interest percentage before acquisition		30.00%
Undivided ownership interest percentage after acquisition		50.00%

Additional ownership interest acquired in certain oil and gas properties.

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Organization and basis of presentation.

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Undivided ownership interest percentage after acquisition.

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Undivided ownership interest percentage before acquisition.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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The number of businesses acquired by the entity during the period.

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Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

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Number of new stock issued during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

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