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v3.25.3

Supplementary Information for Exploration and Production Activities (Tables) | 12 Months Ended
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Sep. 30, 2025
Supplementary Information for Exploration and Production Activities Unaudited [Abstract] |
Schedule of Capitalized Costs Relating to Exploration and Production Activities | Capitalized Costs Relating to Exploration and Production Activities
| At September 30
| 2025 |  | 2024
| (Thousands)
Proved Properties(1) | $ | 7,719,339 |  |  | $ | 7,079,903 |
Unproved Properties | 112,432 |  |  | 200,986 |
| 7,831,771 |  |  | 7,280,889 |
Less — Accumulated Depreciation, Depletion and Amortization | 5,374,360 |  |  | 5,004,299 |
| $ | 2,457,411 |  |  | $ | 2,276,590 |
(1)Includes asset retirement costs of $233.9 million and $175.2 million at September 30, 2025 and 2024, respectively.
Summary of Capitalized Costs of Unproved Properties Excluded from Amortization | Following is a summary of costs excluded from amortization at September 30, 2025:
| Total as of September 30, 2025 |  | Year Costs Incurred
|  | 2025 |  | 2024 |  | 2023 |  | Prior
| (Thousands)
Acquisition Costs | $ | 103,508 |  |  | $ | 1,277 |  |  | $ | 8,136 |  |  | $ | 86,038 |  |  | $ | 8,057 |
Development Costs | 8,464 |  |  | 6,267 |  |  | 1,077 |  |  | 922 |  |  | 198 |
Exploration Costs | 460 |  |  | 460 |  |  | — |  |  | — |  |  | — |
Capitalized Interest | — |  |  | — |  |  | — |  |  | — |  |  | — |
| $ | 112,432 |  |  | $ | 8,004 |  |  | $ | 9,213 |  |  | $ | 86,960 |  |  | $ | 8,255 |
Schedule of Costs Incurred in Property Acquisition, Exploration and Development Activities | Costs Incurred in Property Acquisition, Exploration and Development Activities
| Year Ended September 30
| 2025 |  | 2024 |  | 2023
| (Thousands)
United States |
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 |
| $ | 556,059 |  |  | $ | 565,282 |  |  | $ | 734,138 |
(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.
Schedule of Results of Operations for Producing Activities | Results of Operations for Producing Activities
| Year Ended September 30
| 2025 |  | 2024 |  | 2023
United States | (Thousands, except per Mcfe amounts)
Operating Revenues: |  |  |  |  |
Gas (includes transfers to operations of $1,379, $1,557 and $1,957, respectively)(1) | $ | 1,104,283 |  |  | $ | 738,778 |  |  | $ | 1,036,499 |
Oil, Condensate and Other Liquids | 1,837 |  |  | 2,298 |  |  | 2,261 |
Total Operating Revenues(2) | 1,106,120 |  |  | 741,076 |  |  | 1,038,760 |
Production/Lifting Costs | 284,771 |  |  | 270,927 |  |  | 253,555 |
Franchise/Ad Valorem Taxes | 18,267 |  |  | 13,468 |  |  | 17,532 |
Accretion Expense | 7,721 |  |  | 5,992 |  |  | 5,673 |
Depreciation, Depletion and Amortization ($0.61, $0.69 and $0.63 per Mcfe of production, respectively) | 261,712 |  |  | 270,648 |  |  | 235,694 |
Impairment of Exploration and Production Properties | 108,348 |  |  | 463,692 |  |  | — |
Income Tax Expense (Benefit) | 114,502 |  |  | (76,983) |  |  | 145,574 |
Results of Operations for Producing Activities (excluding corporate overheads and interest charges) | $ | 310,799 |  |  | $ | (206,668) |  |  | $ | 380,732 |
(1)There were no revenues from sales to affiliates for all years presented. (2)Exclusive of hedging gains and losses. See further discussion in Note J — Financial Instruments.
Schedule of Proved Developed and Undeveloped Gas and Oil Reserve Quantities |
| U.S.
| Appalachian Region
| Gas MMcf |  |  |  | Oil Mbbl
Proved Developed and Undeveloped Reserves: |  |  |  |  |
September 30, 2022 | 4,170,662 |  |  |  |  | 250 |
Extensions and Discoveries | 670,438 |  | (1) |  |  | — |
Revisions of Previous Estimates | 32,379 |  |  |  |  | (4) |
Production | (372,271) |  | (2) |  |  | (30) |
Purchases of Minerals in Place | 33,876 |  |  |  |  | — |
September 30, 2023 | 4,535,084 |  |  |  |  | 216 |
Extensions and Discoveries | 601,679 |  | (1) |  |  | — |
Revisions of Previous Estimates | 7,046 |  |  |  |  | 8 |
Production | (392,047) |  | (2) |  |  | (31) |
September 30, 2024 | 4,751,762 |  |  |  |  | 193 |
Extensions and Discoveries | 632,536 |  | (1) |  |  | — |
Revisions of Previous Estimates | 22,469 |  |  |  |  | 15 |
Production | (426,357) |  | (2) |  |  | (28) |
September 30, 2025 | 4,980,410 |  |  |  |  | 180 |
Proved Developed Reserves: |  |  |  |  |
September 30, 2022 | 3,312,568 |  |  |  |  | 250 |
September 30, 2023 | 3,550,034 |  |  |  |  | 216 |
September 30, 2024 | 3,484,852 |  |  |  |  | 193 |
September 30, 2025 | 3,664,381 |  |  |  |  | 180 |
Proved Undeveloped Reserves: |  |  |  |  |
September 30, 2022 | 858,094 |  |  |  |  | — |
September 30, 2023 | 985,050 |  |  |  |  | — |
September 30, 2024 | 1,266,910 |  |  |  |  | — |
September 30, 2025 | 1,316,029 |  |  |  |  | — |
(1)Extensions and discoveries include 163 Bcf (during 2023), 230 Bcf (during 2024) and 0 Bcf (during 2025), of Marcellus Shale gas (which exceed 15% of total reserves) in the Appalachian region. Extensions and discoveries include 507 Bcf (during 2023), 372 Bcf (during 2024) and 633 Bcf (during 2025), of Utica Shale gas (which exceed 15% of total reserves) in the Appalachian region. (2)Production includes 190,290 MMcf (during 2023), 235,955 MMcf (during 2024) and 209,379 MMcf (during 2025), from Marcellus Shale fields. Production includes 180,750 MMcf (during 2023), 154,701 MMcf (during 2024) and 215,681 MMcf (during 2025), from Utica Shale fields.
Schedule of Standardized Measure of Discounted Future Cash Flows Relating to Proved Reserves |
| Year Ended September 30
| 2025 |  | 2024 |  | 2023
| (Thousands)
United States |  |  |  |  |
Future Cash Inflows | $ | 12,243,757 |  |  | $ | 8,514,126 |  |  | $ | 11,947,345 |
Less: |  |  |  |  |
Future Production Costs | 3,823,175 |  |  | 3,672,901 |  |  | 3,538,389 |
Future Development Costs | 1,239,386 |  |  | 1,191,708 |  |  | 1,095,096 |
Future Income Tax Expense at Applicable Statutory Rate | 1,719,387 |  |  | 826,094 |  |  | 1,867,457 |
Future Net Cash Flows | 5,461,809 |  |  | 2,823,423 |  |  | 5,446,403 |
Less: |  |  |  |  |
10% Annual Discount for Estimated Timing of Cash Flows | 2,707,425 |  |  | 1,486,968 |  |  | 2,874,295 |
Standardized Measure of Discounted Future Net Cash Flows | $ | 2,754,384 |  |  | $ | 1,336,455 |  |  | $ | 2,572,108 |
Schedule of Principal Sources of Change in the Standardized Measure of Discounted Future Net Cash Flows | The principal sources of change in the standardized measure of discounted future net cash flows were as follows:
| Year Ended September 30
| 2025 |  | 2024 |  | 2023
| (Thousands)
United States |  |  |  |  |
Standardized Measure of Discounted Future Net Cash Flows at Beginning of Year | $ | 1,336,455 |  |  | $ | 2,572,108 |  |  | $ | 5,448,330 |
Sales, Net of Production Costs | (802,983) |  |  | (456,506) |  |  | (767,487) |
Net Changes in Prices, Net of Production Costs | 1,716,936 |  |  | (1,829,714) |  |  | (3,918,392) |
Extensions and Discoveries | 330,925 |  |  | (11,007) |  |  | 237,057 |
Changes in Estimated Future Development Costs | 58,606 |  |  | 32,990 |  |  | (222,233) |
Purchases of Minerals in Place | — |  |  | — |  |  | 34,346 |
Sales of Minerals in Place | — |  |  | — |  |  | — |
Previously Estimated Development Costs Incurred | 246,309 |  |  | 305,602 |  |  | 342,024 |
Net Change in Income Taxes at Applicable Statutory Rate | (467,758) |  |  | 462,075 |  |  | 959,728 |
Revisions of Previous Quantity Estimates | (7,374) |  |  | 19,216 |  |  | 33,192 |
Accretion of Discount and Other | 343,268 |  |  | 241,691 |  |  | 425,543 |
Standardized Measure of Discounted Future Net Cash Flows at End of Year | $ | 2,754,384 |  |  | $ | 1,336,455 |  |  | $ | 2,572,108 |

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- Definition Tabular disclosure of the aggregate change in the standardized measure of discounted future net cash flows relating to proved oil and gas reserves and oil and gas subject to purchases under long-term agreements in which the enterprise participates in the operation of the properties on which oil and gas is located or otherwise serves as the producer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name Form 20-F -Number Part II -Section Item 18 -Subparagraph (Instruction 2) -Publisher SEC Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 55 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477916/932-235-55-7 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 34 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-34 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 35A -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-35A Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 35 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-35 + Details
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- Definition Tabular disclosure of the net quantities of an enterprise's interests in proved developed and undeveloped reserves of (a) crude oil (including condensate and natural gas liquids), (b) natural gas (including coal bed methane), (c) synthetic oil, (d) synthetic gas, and (e) other nonrenewable natural resources that are intended to be upgraded during the period as of the beginning of the period, changes in quantities during the period, and as of the end of the period. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name Form 20-F -Number Part II -Section Item 18 -Subparagraph (Instruction 2) -Publisher SEC Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-8 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-8 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-7 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 55 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477916/932-235-55-2 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-3 Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-4 Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-8 Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-5 + Details
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- Definition Tabular disclosure of the future net cash flows relating to proved oil and gas reserves and oil and gas subject to purchase under long-term agreements in which the enterprise participates in the operation of the properties on which the oil and gas is located or otherwise serves as the producer. This information is presented in aggregate and for each geographic area for which reserve quantities are disclosed. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name Form 20-F -Number Part II -Section Item 18 -Subparagraph (Instruction 2) -Publisher SEC Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 55 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477916/932-235-55-6 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 29 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-29 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Name Accounting Standards Codification -Section 50 -Paragraph 31 -SubTopic 235 -Topic 932 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-31 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Name Accounting Standards Codification -Section 50 -Paragraph 33 -SubTopic 235 -Topic 932 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-33 + Details
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