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Commitments and Contingencies - Table (Details) $ in Millions | Sep. 30, 2023 USD ($) megawatts | Sep. 30, 2022 USD ($) | Sep. 30, 2021 USD ($)
--- | --- | --- | ---
Obligations |  |  |  |
Megawatts provided under transmission obligations | megawatts |  | 2,792 |  |
Accrual for Environmental Loss Contingencies, Gross |  | $ 16 | $ 17 |
Estimated future decommissioning cost | [1] | 7,489 | 7,162 | $ 7,002
Nuclear |  |  |  |
Obligations |  |  |  |
Estimated future decommissioning cost |  | $ 3,808 | $ 3,643 | $ 3,428
[1] | (1) Includes $272 million and $275 million at September 30, 2023 and 2022, respectively, in Current liabilities.

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