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Financial Instruments - Narrative (Details) Bcf in Billions | 12 Months Ended | 36 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2024 USD ($) counterparty Bcf | Dec. 31, 2023 USD ($) | Dec. 31, 2025 USD ($) payment | Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | Jun. 30, 2022 USD ($) | Sep. 30, 2021 USD ($)
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |
Foreign currency forward contracts duration maximum | 6 years |  |  |  |  |  |
After tax net hedging gains in accumulated other comprehensive income (loss) | $ 55,800,000 |  |  |  |  |  |
After tax net hedging gains reclassified within twelve months | 33,300,000 |  |  |  |  |  |
Fair market value of derivative liability with a credit-risk related contingency | 0 |  |  |  |  |  |
Hedging collateral deposits | 0 |  |  | $ 0 | $ 91,670,000 |  | $ 88,610,000
Foreign Currency Contracts |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |
Hedging notional amount of forecasted transportation costs | $ 51,200,000 |  |  |  |  |  |
Over the Counter Swaps, No Cost Collars and Foreign Currency Forward Contracts |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |
Number of counterparties in which the company holds over-the-counter swap positions | counterparty | 19 |  |  |  |  |  |
Number of counterparties in net gain position | counterparty | 17 |  |  |  |  |  |
Credit risk exposure per counterparty | $ 5,100,000 |  |  |  |  |  |
Maximum credit risk exposure per counterparty | 18,900,000 |  |  |  |  |  |
Collateral received by company | $ 0 |  |  |  |  |  |
Number of counterparties with a common credit-risk related contingency | counterparty | 16 |  |  |  |  |  |
California Asset Sale | Forecast |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [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 | Present Value of Contingent Consideration |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |
Value of contingent consideration received from sale of assets | $ 700,000 |  |  | $ 7,300,000 |  | $ 12,600,000 |
California Asset Sale | Mark to Market of Contingent Consideration |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |
Mark-to-market adjustment for contingent consideration | $ (6,600,000) |  |  |  |  |  |
California Asset Sale | Minimum |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |
ICE Brent Average (in dollars per barrel) |  | $ 95 |  |  |  |  |
California Asset Sale | Minimum | Forecast |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |
ICE Brent Average (in dollars per barrel) |  |  | $ 95 |  |  |  |
California Asset Sale | Maximum | Forecast |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |
Number of annual contingent payments | payment |  |  | 3 |  |  |  |
ICE Brent Average (in dollars per barrel) |  |  | $ 105 |  |  |  |
Cash Flow Hedges |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |
Hedge duration | 5 years |  |  |  |  |  |
Cash Flow Hedges | Natural Gas Bcf |  |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |
Nonmonetary notional amount of price risk cash flow hedge derivatives, natural gas (in Bcf) | Bcf | 349.4 |  |  |  |  |  |

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