Income Taxes (Income Tax Expense Reconciliation) (Details) - USD ($) $ in Millions	12 Months Ended
Oct. 01, 2021	Oct. 02, 2020	Sep. 27, 2019
Income Tax Disclosure [Abstract]
Tax expense at United States statutory rate	$ 335.7	$ 187.3	$ 201.8
Foreign tax rate difference	(155.2)	(86.6)	(115.3)
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount	0.0	0.2	8.1
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Amount	(13.5)	(10.3)	(1.6)
Research and development credits	(27.0)	(23.0)	(25.7)
Change in tax reserve	(51.5)	9.6	18.4
EffectiveIncomeTaxRateReconciliationGlobalIntangibleLowTaxedIncomeAmount	69.0	35.9	54.3
EffectiveIncomeTaxRateReconciliationForeignDerivedIntangibleIncome	(79.7)	(41.2)	(41.5)
Other, net	22.6	5.0	9.0
Provision for income taxes	$ 100.4	$ 76.9	$ 107.4

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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