Commitments And Contingencies (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 27, 2024	Sep. 29, 2023	Sep. 30, 2022
Supply Commitment [Line Items]
Asset impairment charges	$ 147.9	$ 64.5	$ 20.7
Recorded Unconditional Purchase Obligation [Line Items]
Prepaid expenses, current	234.8	306.0
Supply capacity deposits
Supply Commitment [Line Items]
Asset impairment charges		47.5
Wafer purchases
Recorded Unconditional Purchase Obligation [Line Items]
Deposits assets, current	141.7	41.7
Prepaid expenses, current	3.0	1.3
Deposits assets, noncurrent	1.3
Prepaid expenses, noncurrent	$ 21.8	$ 16.0

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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