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v3.25.3

Plant Closures (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Completed Plant |  |  |  |
Depreciation |  | $ 1,900 | $ 1,800 | $ 1,900
Accumulated depreciation | $ 38,716 | 38,716 | $ 38,793 |
Cumberland |  |  |  |
Property, Plant and Equipment [Abstract] |  |  |  |
Accelerated depreciation | 16 | 176 |  |
Completed Plant |  |  |  |
Accelerated depreciation | 16 | 176 |  |
Kingston |  |  |  |
Property, Plant and Equipment [Abstract] |  |  |  |
Accelerated depreciation | 9 | 54 |  |
Completed Plant |  |  |  |
Accelerated depreciation | $ 9 | $ 54 |  |
Property, Plant and Equipment [Member] |  |  |  |
Completed Plant |  |  |  |
Property, Plant and Equipment, Dispositions |  | 15 million | 15 million | 14 million

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