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Fair Value Measurements - Schedule of Significant Unobservable Inputs Used to Value Level 3 Instruments (Details 2) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 USD ($) $ / MMBTU $ / MWh | Dec. 31, 2024 USD ($) $ / MWh $ / MMBTU
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments |  |
Assets | $ 1,845,615 | $ 1,707,783
Level 3 |  |
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments |  |
Assets | 1,369 | 7,176
Level 3 | Forward Contracts | Commodity Contracts |  |
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments |  |
Assets | 1,369 | 7,176
Liabilities | $ 19,645 | $ 22,215
Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | Commodity Contracts | Minimum |  |
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments |  |
Electricity forward price (per megawatt-hour (“MWh”)) | $ / MWh | 30.85 | 25.25
Natural gas forward price (per Million British Thermal Units (“MMBtu”)) | $ / MMBTU | 0.48 | (0.89)
Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | Commodity Contracts | Maximum |  |
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments |  |
Electricity forward price (per megawatt-hour (“MWh”)) | $ / MWh | 157.99 | 151.11
Natural gas forward price (per Million British Thermal Units (“MMBtu”)) | $ / MMBTU | 0.1 | 1.47
Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | Commodity Contracts | Weighted Average |  |
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments |  |
Electricity forward price (per megawatt-hour (“MWh”)) | $ / MWh | 80.98 | 106.06
Natural gas forward price (per Million British Thermal Units (“MMBtu”)) | $ / MMBTU | (0.09) | 0.71
Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | Electricity: | Commodity Contracts |  |
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments |  |
Assets | $ 1,032 | $ 708
Liabilities | 17,576 | 21,890
Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | Natural Gas: | Commodity Contracts |  |
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments |  |
Assets | 337 | 6,468
Liabilities | $ 2,069 | $ 325

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