Supplemental Balance Sheet Information (Prepaid Expenses and Other Current Assets) (Details) - USD ($) $ in Millions	Jun. 27, 2021	Sep. 27, 2020
Prepaid Expenses and Other Current Assets [Line Items]
Income tax receivable	$ 67.9	$ 356.9
Government subsidies receivables	161.7	155.1
Other prepaid expenses and current assets	336.0	227.5
Prepaid expenses and other current assets	$ 565.6	$ 739.5

[Line Items] for Prepaid Expenses and Other Current Assets [Table]

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Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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Amount of asset related to consideration paid in advance for other costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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