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Plant Closures (Details) - USD ($) $ in Millions | 3 Months Ended | 18 Months Ended
--- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Jun. 30, 2024
Property, Plant and Equipment [Line Items] |  |  |
Depreciation expense | $ 471 | $ 452 |
Cumberland |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Accelerated depreciation | $ 16 |  |
Accumulated additional depreciation |  |  | $ 128

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