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v3.25.3

Revenue Local Power Company Contracts (Details) $ in Millions | 12 Months Ended
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Sep. 30, 2025 USD ($) Units | Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($)
Electric revenue | $ 13,483 | $ 12,123 | $ 11,888
Total number of LPCs | Units | 153 |  |
Percentage of total operating revenues | 90.20% |  |
Percent of wholesale Credit offered | 3.10% |  |
Pandemic Relief Credit | $ 225 |  |
Local Power Company [Member] |  |  |
Electric revenue | $ 12,334 |  |
5-year contract arrangement [Member] |  |  |
Number of LPCs signed LTA | Units | 5 |  |
Percentage of total operating revenues | 12.40% |  |

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- Definition Number of LPCs signed LTA + References No definition available. + Details
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- Definition Pandemic Relief Credit + References No definition available. + Details
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- Definition Percent of wholesale Credit offered + References No definition available. + Details
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- Definition Percentage of total operating revenues + References No definition available. + Details
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- Definition Total number of LPCs + References No definition available. + Details
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- Details
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- Details
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