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Income Taxes - Income Tax Rate Reconciliation (Details) | 12 Months Ended
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Oct. 03, 2021 | Sep. 27, 2020 | Sep. 29, 2019
Income Tax Disclosure [Abstract] |  |  |
Tax at federal statutory rate | 21.00% | 21.00% | 21.00%
State taxes, net of federal benefit | 2.30% | 2.70% | 3.30%
Research and Development ("R&D") credits | (2.60%) | (2.20%) | (4.70%)
Tax differential on foreign earnings | 0.90% | 0.70% | 1.00%
Non-taxable foreign interest income | (1.00%) | (1.10%) | (1.70%)
Goodwill | 0.00% | 1.50% | 0.90%
Stock compensation | (3.30%) | (2.20%) | (2.40%)
Valuation allowance | (9.30%) | 1.60% | (13.50%)
Change in uncertain tax positions | 1.70% | 0.40% | 2.40%
Return to provision | (3.70%) | 0.80% | (0.20%)
Disallowed officer compensation | 2.00% | 0.20% | 0.20%
Cash repatriation | 2.10% | 0.00% | 0.00%
Unremitted earnings | 1.00% | 0.00% | 0.00%
Revaluation of deferred taxes | 0 | 0 | (0.014)
Deferred tax adjustments | 0.80% | (1.30%) | (0.40%)
Transition taxes on foreign earnings | 0 | 0 | 0.014
Other | 0.90% | 1.60% | 3.40%
Total income tax expense | 12.80% | 23.70% | 9.30%

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