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v3.24.3

Supplementary Information for Exploration and Production Activities - Narrative (Details) $ in Millions, Bcf in Billions | 12 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2024 USD ($) pUDLocation Bcf | Sep. 30, 2023 USD ($) pUDLocation Bcf | Sep. 30, 2022 USD ($) Bcf | Sep. 30, 2021 | Sep. 30, 2020
Reserve Quantities [Line Items] |  |  |  |  |
Amount spent for developing proved undeveloped reserves | $ | $ 305.6 | $ 342.0 | $ 154.3 |  |
Proved undeveloped reserve volume (in Bcfe) | 1,267 | 985 | 858 |  |
Percentage of PUD reserves to the total proved reserves | 26.70% | 21.70% | 20.60% |  |
Increase in PUD reserves (in Bcfe) | 282 | 127 |  |  |
New PUD reserve additions (in Bcfe) | 602 | 554 |  |  |
PUD reserves added back (in Bcfe) |  | 14 |  |  |
Number of PUD wells added back | pUDLocation |  | 1 |  |  |
PUD upward revisions (in Bcfe) | 76 | 23 |  |  |
PUD conversions to developed reserves (in Bcfe) | 291 | 402 |  |  |
Proved undeveloped reserves removed (in Bcfe) | 105 | 62 |  |  |
Number of PUD well locations removed | pUDLocation | 9 | 7 |  |  |
Investment made to convert proved undeveloped reserves to developed reserves | $ | $ 306.0 | $ 342.0 |  |  |
Conversion of undeveloped proved reserves to developed proved reserves after revisions (in Bcfe) | 374 | 440 |  |  |
Conversion of PUD to developed to PUD reserves booked at end of prior year (as a percent) | 30.00% | 47.00% | 45.00% | 34.00% | 36.00%
Arbitrary discount rate (as a percent) | 10.00% |  |  |  |
Total PUD Reserve Additions Estimated in the Next Fiscal Year |  |  |  |  |
Reserve Quantities [Line Items] |  |  |  |  |
Amount to be spent on developing proved undeveloped reserves | $ | $ 300.0 |  |  |  |
Utica Shale |  |  |  |  |
Reserve Quantities [Line Items] |  |  |  |  |
Proved undeveloped reserve volume (in Bcfe) | 925 | 873 | 503 |  |
PUD conversions to developed reserves (in Bcfe) |  | 127 |  |  |
Marcellus Shale Fields |  |  |  |  |
Reserve Quantities [Line Items] |  |  |  |  |
Proved undeveloped reserve volume (in Bcfe) | 342 | 112 | 355 |  |
PUD conversions to developed reserves (in Bcfe) |  | 275 |  |  |
Appalachian Region |  |  |  |  |
Reserve Quantities [Line Items] |  |  |  |  |
Number of well locations developed with net PUD reserves | pUDLocation | 20 | 39 |  |  |
Number of well locations to be developed with net PUD reserves | pUDLocation | 73 | 77 |  |  |

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