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Supplemental Disclosures about Oil and Natural Gas Producing Properties (unaudited) - Narrative (Details) |  | 12 Months Ended
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Jun. 24, 2016 USD ($) | Jun. 30, 2017 USD ($) Mcf bbl | Jun. 30, 2016 USD ($) Mcf bbl | Jun. 30, 2015 USD ($) Mcf bbl
Reserve Quantities [Line Items] |  |  |  |  |  |  |
Oil and natural gas property costs attributable to the recognition of asset retirement obligations | $ |  | $ 471,864 |  | $ 140,151 |  | $ 576,039 |
Fair value of litigation settlement | $ |  | $ 0 |  | $ 596,500 |  | $ 0 |
Period Considered for Unweighted Arithmetic Average for Determining Reserve Volumes and Values |  | 12 months |  |  |  |  |
Period Considered for Determining Unweighted Arithmetic Average of First Day of Month, Commodity Prices |  | 12 months |  |  |  |  |
Natural Gas |  |  |  |  |  |  |
Reserve Quantities [Line Items] |  |  |  |  |  |  |
Revision increase(decrease) of previous estimates (in Bbls/Mcf) | Mcf |  | 16 | [1] | (3,319) | [2] | (2,894,703) | [3]
Natural Gas Liquids |  |  |  |  |  |  |
Reserve Quantities [Line Items] |  |  |  |  |  |  |
Revision increase(decrease) of previous estimates (in Bbls/Mcf) | bbl |  | (504,733) | [1] | (198,233) | [2] | 156,195 | [3]
Revision due to improved design (in Bbls/Mcf) | bbl |  |  |  |  |  | 185,499 |
Delhi Field | Natural Gas |  |  |  |  |  |  |
Reserve Quantities [Line Items] |  |  |  |  |  |  |
Revision increase(decrease) of previous estimates (in Bbls/Mcf) | Mcf |  |  |  |  |  | (2,246,524) |
Giddings Field | Natural Gas |  |  |  |  |  |  |
Reserve Quantities [Line Items] |  |  |  |  |  |  |
Revision increase(decrease) of previous estimates (in Bbls/Mcf) | Mcf |  |  |  |  |  | (452,786) |
Giddings Field | Natural Gas Liquids |  |  |  |  |  |  |
Reserve Quantities [Line Items] |  |  |  |  |  |  |
Revision increase(decrease) of previous estimates (in Bbls/Mcf) | bbl |  |  |  |  |  | (29,304) |
Dehli Field Litigation | Denbury Resources, Inc |  |  |  |  |  |  |
Reserve Quantities [Line Items] |  |  |  |  |  |  |
Working interest in Mengal Sand Interval | 23.90% |  |  |  |  |  |
Fair value of litigation settlement | $ | $ 596,500 |  |  |  |  |  |
[1] | The positive crude oil revision resulted from better production performance during fiscal 2017 and the expectation of greater ultimate recoveries of oil from the Delhi field. The negative NGL revision results primarily from lower expectations for ultimate NGL recoveries from the plant based on production data after the plant commenced production.
[2] | The negative revision results primarily from the removal of proved undeveloped reserves in the far eastern part of the Delhi field, referred to as Test Site 6, which were deemed uneconomic under the lower SEC price case utilized at the end of the period.
[3] | The 2,894,703 revision for natural gas in fiscal 2015 primarily reflects a 2,246,524 MCF reduction for the Delhi field NGL plant together with a 452,786 MCF revision at the Giddings Field for a well that was lost due to mechanical issues. The NGL plant revision resulted from a decision to change in the plant design to use the methane production internally to reduce field operating costs rather than selling it into the market. The 156,195 BBL positive natural gas liquids revision primarily reflects 185,499 BBL positive revision for better recovery from the redesigned NGL plant, partly offset by a 29,304 BBL negative revision from the lost Giddings well.

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