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v3.24.3

Plant Closures (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended | 57 Months Ended
--- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023
Property, Plant and Equipment [Abstract] |  |  |  |  |
Accelerated depreciation |  |  | $ 177 | $ 140 | $ 659
Completed Plant |  |  |  |  |
Accelerated depreciation |  |  | 177 | 140 | 659
Depreciation |  | $ 1,800 | 1,900 | $ 1,800 |
Accumulated depreciation | $ 38,793 | 38,793 | $ 35,871 |  | $ 35,871
Cumberland |  |  |  |  |
Property, Plant and Equipment [Abstract] |  |  |  |  |
Accelerated depreciation | 16 | 112 |  |  |
Completed Plant |  |  |  |  |
Accelerated depreciation | 16 | 112 |  |  |
Kingston |  |  |  |  |
Property, Plant and Equipment [Abstract] |  |  |  |  |
Accelerated depreciation | 9 | 18 |  |  |
Completed Plant |  |  |  |  |
Accelerated depreciation | $ 9 | $ 18 |  |  |
Property, Plant and Equipment [Member] |  |  |  |  |
Completed Plant |  |  |  |  |
Property, Plant and Equipment, Dispositions |  | 15 million | 14 million | 22 million |

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