Property and Equipment - Schedule of oil and natural gas properties and other property and equipment (Details) - USD ($)	6 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2019
Oil and natural gas properties
Property costs subject to amortization	$ 106,951,180		$ 95,622,153
Less: Accumulated depreciation, depletion, and amortization	(38,136,611)		(35,275,687)
Unproved properties not subject to amortization	0		0
Oil and natural gas properties, net	68,814,569		60,346,466
Other property and equipment
Furniture, fixtures, office equipment and other, at cost	154,731		154,731
Less: Accumulated depreciation	(132,817)		(128,313)
Other property and equipment, net	21,914		$ 26,418
Delhi field
Other property and equipment
Capital expenditures	$ 1,100,000	$ 4,000,000

Future cash outflow to pay for purchases of fixed assets that have occurred.

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The sum of the capitalized costs incurred, as of the balance sheet date, of unproved properties excluded from amortization including acquisition costs, exploration costs, development costs, and production costs.

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Oil and gas properties, gross, carried under the full cost method.

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Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale.

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