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v3.25.3

Supplementary Information for Exploration and Production Activities - Costs Incurred in Property Acquisition, Exploration and Development Activities (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Property Acquisition Costs: |  |  |  |
Proved |  | $ 13,680 | $ 17,069 | $ 33,190
Unproved |  | 18,826 | 19,526 | 129,061
Exploration Costs | [1] | 21,562 | 53,519 | 10,055
Development Costs | [2] | 443,311 | 429,151 | 553,469
Asset Retirement Costs |  | 58,680 | 46,017 | 8,363
Total Property Acquisition Costs |  | 556,059 | 565,282 | 734,138
Capitalized interest included in exploration costs |  | 0 | 100 | 0
Capitalized interest included in development costs |  | $ 0 | $ 700 | $ 100
[1] | Amounts for 2025, 2024 and 2023 include capitalized interest of zero, $0.1 million and zero respectively.
[2] | Amounts for 2025, 2024 and 2023 include capitalized interest of zero, $0.7 million and $0.1 million, respectively.

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- Definition Amount of acquisition cost incurred for property with proved and unproved reserves in oil- and gas-producing activities. Includes capitalized cost and cost charged to expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 20 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-20 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 20 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-20 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 19 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-19 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-18 + Details
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- Definition Amount of acquisition cost incurred for property with unproved reserve in oil- and gas-producing activities. Includes capitalized cost and cost charged to expense. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 55 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477916/932-235-55-4 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 19 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-19 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-17 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-18 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 20 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-20 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 20 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-20 + Details
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- Definition Amount of development cost incurred in oil- and gas-producing activities. Includes capitalized cost and cost charged to expense. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 55 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477916/932-235-55-4 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-17 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 20 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-20 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 20 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-20 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 19 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-19 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-18 + Details
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