The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
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-Topic 932
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-10(c)(3)(ii)(A))
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The sum of the capitalized costs incurred during the period of unproved properties excluded from amortization including acquisition costs, exploration costs, development costs, and production costs.

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The capitalized costs incurred during the period (excluded from amortization) to obtain access to proved reserves and to provide facilities for extracting, treating, gathering and storing the oil and gas.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
-Paragraph 1
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The capitalized costs incurred during the period (excluded from amortization) in identifying areas that may warrant examination and in examining specific areas that are considered to have prospects of containing oil and gas reserves, including costs of drilling exploratory wells and exploratory-type stratigraphic test wells. Exploration costs may be incurred both before acquiring the related property (sometimes referred to in part as prospecting costs) and after acquiring the property. Principal types of exploration costs, which include depreciation and applicable operating costs of support equipment and facilities and other costs of exploration activities, are: costs of topographical, geographical and geophysical studies, rights of access to properties to conduct those studies, and salaries and other expenses of geologists, geophysical crews, and others conducting those studies. Collectively, these are sometimes referred to as geological and geophysical or "G&G" costs. Exploration costs also include costs of carrying and retaining undeveloped properties, such as delay rentals, ad valorem taxes on properties, legal costs for title defense, the maintenance of land and lease records, dry hole contributions and bottom hole contributions, costs of drilling and equipping exploratory wells and costs of drilling exploratory-type stratigraphic test wells.

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Amount of interest capitalized during the period.

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-Topic 835
-SubTopic 20
-Section 50
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Supplementary Information For Oil And Gas Producing Activities (Summary Of Capitalized Costs Of Unproved Properties Excluded From Amortization) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Acquisition Costs	$ 0	$ 32,762	$ 0
Development Costs	14,979	2,430	17,114
Exploration Costs	572	0	0
Capitalized Interest	340	496	41
Capitalized Costs of Unproved Properties Excluded from Amortization, Total	15,891	$ 35,688	$ 17,155
Capitalized Costs Of Unproved Properties Cumulative Balance [Member]
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Acquisition Costs	57,027
Development Costs	37,574
Exploration Costs	8,178
Capitalized Interest	980
Capitalized Costs of Unproved Properties Excluded from Amortization, Total	$ 103,759
Costs Incurred Prior To Fiscal 2019 [Member]
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Acquisition Costs				$ 24,265
Development Costs				3,051
Exploration Costs				7,606
Capitalized Interest				103
Capitalized Costs of Unproved Properties Excluded from Amortization, Total				$ 35,025