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Acquisition - Narrative (Details) - GLT Acquisition - Berry Global Group, Inc. - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
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Mar. 30, 2024 | Mar. 29, 2025 | Mar. 30, 2024
Asset Acquisition [Line Items] |  |  |
Business acquisition, pro forma net sales | $ 885 | $ 1,638 | $ 1,725
Business acquisition, pro forma loss | $ 25 | $ 110 | $ 60

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