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Asset Acquisitions and Divestitures - Narrative (Details) |  |  | 12 Months Ended | 36 Months Ended
--- | --- | --- | --- | ---
Jun. 01, 2023 USD ($) a | Jun. 30, 2022 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2023 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | Dec. 31, 2025 USD ($) payment
Asset Acquisition [Line Items] |  |  |  |  |  |  |
Net Proceeds from Sale of Exploration and Production Properties |  |  | $ 0 |  | $ 0 | $ 254,439,000 |
Gain on Sale of Assets |  |  | 0 |  | 0 | 12,736,000 |
Reduction in asset retirement obligation |  |  | 25,556,000 |  | 14,448,000 | $ 71,171,000 |
California Asset Sale |  |  |  |  |  |  |
Asset Acquisition [Line Items] |  |  |  |  |  |  |
Total sale price |  | $ 253,500,000 |  |  |  |  |
Net Proceeds from Sale of Exploration and Production Properties |  | 240,900,000 |  |  |  |  |
Gain on Sale of Assets |  | 12,700,000 |  |  |  |  |
Reduction in asset retirement obligation |  | 50,100,000 |  |  |  |  |
California Asset Sale | Forecast |  |  |  |  |  |  |
Asset Acquisition [Line Items] |  |  |  |  |  |  |
Maximum annual contingent payment |  |  |  |  |  |  | $ 10,000,000
Amount of each incremental contingency payment |  |  |  |  |  |  | 1,000,000
Incremental price, exceeding ICE Brent Average Price (in dollars per barrel) |  |  |  |  |  |  | 1
California Asset Sale | Full Cost Method of Accounting Assets |  |  |  |  |  |  |
Asset Acquisition [Line Items] |  |  |  |  |  |  |
Disposal of assets |  | 220,700,000 |  |  |  |  |
California Asset Sale | Assets Not Subject to Full Cost Method of Accounting |  |  |  |  |  |  |
Asset Acquisition [Line Items] |  |  |  |  |  |  |
Disposal of assets |  | 32,800,000 |  |  |  |  |
California Asset Sale | Minimum |  |  |  |  |  |  |
Asset Acquisition [Line Items] |  |  |  |  |  |  |
ICE Brent Average (in dollars per barrel) |  |  |  | $ 95 |  |  |
California Asset Sale | Minimum | Forecast |  |  |  |  |  |  |
Asset Acquisition [Line Items] |  |  |  |  |  |  |
ICE Brent Average (in dollars per barrel) |  |  |  |  |  |  | $ 95
California Asset Sale | Maximum | Forecast |  |  |  |  |  |  |
Asset Acquisition [Line Items] |  |  |  |  |  |  |
Number of annual contingent payments | payment |  |  |  |  |  |  | 3
ICE Brent Average (in dollars per barrel) |  |  |  |  |  |  | $ 105
California Asset Sale | Present Value of Contingent Consideration |  |  |  |  |  |  |
Asset Acquisition [Line Items] |  |  |  |  |  |  |
Value of contingent consideration received from sale of assets |  | $ 12,600,000 | $ 700,000 |  | $ 7,300,000 |  |
SWN Upstream Asset Acquisition |  |  |  |  |  |  |
Asset Acquisition [Line Items] |  |  |  |  |  |  |
Total consideration | $ 124,758,000 |  |  |  |  |  |
Net acres acquired in Appalachia | a | 34,000 |  |  |  |  |  |

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