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Non producing minerals book value net.

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Number of tracts owned.

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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.

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Summary Of Significant Accounting Policies (Narrative) (Details)	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2018	Sep. 30, 2020 USD ($) a Item $ / a	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of Oil, NGL and Natural Gas Production Units \| Item			6,510
Oil, NGL and natural gas revenues were derived from the sale of natural gas			44.00%
Oil, NGL and natural gas revenues were derived from the sale of oil			48.00%
Oil, NGL and natural gas revenues were derived from the sale of NGL			8.00%
Bad debt expense			$ 0	$ 0	$ 0
Book value of Non-producing oil and natural gas			$ 13,556,020	9,673,787
Percentage of perpetual ownership of mineral interests in Oklahoma, North Dakota, Texas, Arkansas and New Mexico			91.00%
Accumulated period perpetual rights			94 years
Non Producing Minerals Area \| a			190,990
Number of tracts owned \| Item			6,380
Amount of acres average tract contains \| a			30
Tracts Average Cost Per Acre \| $ / a			71
Amortized Period of Non-producing Minerals			33 years
Straight-line amortized period of Producing Minerals			20 years
Straight-line amortized period of insignificant fields			10 years
Amount of Capitalized Interest Included in the Company's Capital Expenditures			$ 0	38,606	89,023
Interest Expense			$ 1,286,788	$ 1,995,789	1,748,101
U.S. federal corporate tax rate	35.00%	21.00%	21.00%
Remeasurement of deferred income tax benefit, amount					$ 12,464,000
Effective tax rate			(26.00%)	(25.00%)
One-time Severance [Member]
Summary Of Significant Accounting Policies [Line Items]
Decrease in accrued compensation				$ (670,000)
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life of furniture and fixtures			5 years
Restricted Stock Awards, vesting period			3 years
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life of furniture and fixtures			8 years
Sales Revenue, Net [Member] \| Product Concentration Risk [Member] \| Oil [Member]
Summary Of Significant Accounting Policies [Line Items]
Total sale volume from sale of Oil, NGL and Natural gas			19.00%
Sales Revenue, Net [Member] \| Product Concentration Risk [Member] \| NGL [Member]
Summary Of Significant Accounting Policies [Line Items]
Total sale volume from sale of Oil, NGL and Natural gas			12.00%
Sales Revenue, Net [Member] \| Product Concentration Risk [Member] \| Natural Gas [Member]
Summary Of Significant Accounting Policies [Line Items]
Total sale volume from sale of Oil, NGL and Natural gas			69.00%