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Acquisition - Narrative (Details) - GLT Acquisition - Berry Global Group, Inc. - USD ($) $ in Millions | 3 Months Ended
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Dec. 28, 2024 | Dec. 30, 2023
Asset Acquisition [Line Items] |  |
Business acquisition, pro forma net sales | $ 814 | $ 839
Business acquisition, pro forma loss | $ 79 | $ 35

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