Area of mineral acreage sold.

No definition available.

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- Definition

Percentage of net mineral acreage sold.

+ References

No definition available.

+ Details

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- Definition

Percentage of net mineral acreage sold on overall production.

+ References

No definition available.

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- Definition

Percentage of net mineral acreage sold on overall revenues.

+ References

No definition available.

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- Definition

Percentage of net mineral acreage sold on proved reserves.

+ References

No definition available.

+ Details

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- Definition

Sale price per acre.

+ References

No definition available.

+ Details

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- Definition

Oil and gas properties net of accumulated depreciation, depletion, amortization, impairment, and abandonment, carried under the successful effort method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61901-109447

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-10.(b))
-URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862

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- Definition

The cash inflow to dispose of long-lived, physical assets and mineral interests in oil and gas properties used for normal oil and gas operations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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Subsequent Events (Narrative) (Details)		12 Months Ended
Subsequent Events (Narrative) (Details)	Nov. 30, 2018 USD ($) a $ / a	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)
Subsequent Event [Line Items]
Proceeds from sales of assets		$ 1,085,137	$ 723,700	$ 4,501,726
Net book value of minerals		$ 198,284,401	$ 196,584,358
Lea and Eddy Counties, New Mexico [Member]
Subsequent Event [Line Items]
Percentage of net mineral acreage sold		0.08%
Percentage of net mineral acreage sold on overall production		0.70%
Percentage of net mineral acreage sold on overall revenues		0.90%
Percentage of net mineral acreage sold on proved reserves		1.20%
Net book value of minerals		$ 0
Subsequent Event [Member] \| Lea and Eddy Counties, New Mexico [Member]
Subsequent Event [Line Items]
Mineral acreage sold \| a	206
Proceeds from sales of assets	$ 9,300,000
Sale price per acre \| $ / a	45,000