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Summary of Significant Accounting Policies (Details) | 12 Months Ended |
--- | --- | ---
Jun. 30, 2018 USD ($) | Jun. 30, 2017 USD ($)
Accounting Policies [Abstract] |  |
Allowance for doubtful accounts | $ 0 | $ 0
Oil and natural gas properties |  |
Limitation on Capitalized Costs |  |
Period considered for computing unweighted arithmetic average of oil and natural gas prices (in months) | 12 months |
Other Property and Equipment | Minimum |  |
Other Property and Equipment |  |
Expected lives of the individual assets or group of assets | 3 years |
Other Property and Equipment | Maximum |  |
Other Property and Equipment |  |
Expected lives of the individual assets or group of assets | 7 years |
Discount rate | Oil and natural gas properties |  |
Limitation on Capitalized Costs |  |
Discount rate for present value (as a percent) | 0.10 |

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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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