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Derivatives, Hedging Programs and Other Financial Instruments - Summary of Volume of Derivative and or Physical Delivery Commitments with Energy Companies (Details) - Scenario, Forecast | Dec. 31, 2026 | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
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Natural Gas |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |
Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage | 20.00% | 20.00% | 44.00% | 48.00% | 49.00% | 44.00%
Electricity |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |
Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage |  |  |  | 44.00% | 76.00% | 94.00%

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