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Unaudited Supplemental Oil and Gas Information - Schedule of Proved Oil and Gas Reserves and Changes in Net Proved Reserves (Details) - bbl | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Oil (bbls) [Member] |  |  |
Reserve quantities, beginning of year |  | 676,030 | 657,280
Revisions of previous estimates |  | 88,956 | 302,530
Discoveries and extensions |  | 61,277 | 22,802
Sale of minerals in place |  |  | (194,667)
Production |  | (75,003) | (111,915)
Reserve quantities, end of year |  | 751,260 | 676,030
Natural Gas (MMbtu) [Member] |  |  |
Reserve quantities, beginning of year | [1] | 888,507 |
Revisions of previous estimates | [1] | 58,177 |
Discoveries and extensions | [1] | 78,007 |
Sale of minerals in place | [1] |  |
Production | [1] | (286,692) |
Reserve quantities, end of year | [1] | 737,998 | 888,507
Natural Gas (mcfe) [Member] |  |  |
Reserve quantities, beginning of year | [1] | 888,507 | 1,379,163
Revisions of previous estimates | [1] |  | 55,072
Discoveries and extensions | [1] |  | 21,787
Sale of minerals in place | [1] |  | (118,944)
Production | [1] |  | (448,571)
Reserve quantities, end of year | [1] |  | 888,507
[1] | Mcf equivalents (Mcfe) consist of natural gas reserves in mcf plus NGLs converted to mcf using a factor of 6 mcf for each barrel of NGL.

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- Definition Additions to proved reserves that result from (1) extension of the proved acreage of previously discovered (old) reservoirs through additional drilling in periods after discovery and (2) discovery of new fields with proved reserves or of new reservoirs of proved reserves in old fields. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 5 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
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- Definition The net quantity of proved reserves as of the balance sheet date. Proved oil reserves are the estimated quantities of crude oil and natural gas liquids which geological and engineering data demonstrate with reasonable certainty to be recoverable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61797-109447 + Details
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- Definition Production of proved reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 5 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
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- Definition Revisions represent changes in previous estimates of proved reserves, either upward or downward, resulting from new information (except for an increase in proved acreage) normally obtained from development drilling and production history or resulting from change in economic factors. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
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- Definition Sales of minerals in place. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
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