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Income Taxes - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Oct. 03, 2021 | Oct. 03, 2021 | Sep. 27, 2020 | Sep. 29, 2019 | Sep. 30, 2018
Operating Loss Carryforwards [Line Items] |  |  |  |  |
Effective tax rate |  | 12.80% | 23.70% | 9.30% |
Reduction in income tax expense due to excess tax benefits on share-based payments |  | $ 12,900 | $ 8,300 | $ 6,400 |
Effective tax rates, excluding valuation allowance release, non-deductible goodwill impairment charge, transaction costs, and excess tax benefits on share-based payments |  | 25.70% | 25.60% | 24.60% |
Deferred tax liabilities for undistributed foreign earnings | $ 3,136 | $ 3,136 | $ 0 |  |
Undistributed earnings of foreign subsidiaries | 50,900 | 50,900 |  |  |
Valuation allowance | 13,040 | 13,040 | 24,395 |  |
Unrecognized tax benefits | 12,899 | 12,899 | 9,228 | $ 9,169 | $ 8,328
Accrual of additional interest and penalties |  | 800 | 800 | 2,600 |
Reduction in accrued interest and penalties |  | 0 | 0 | 200 |
Amount of interest and penalties accrued | 5,200 | 5,200 | 4,400 | $ 3,600 |
Canada |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |
Foreign earnings repatriated | 80,000 |  |  |  |
Tax expense related to repatriation of foreign earnings | 5,600 |  |  |  |
Undistributed foreign earnings no longer indefinitely reinvested | 20,100 | 20,100 |  |  |
Deferred tax liabilities for undistributed foreign earnings | 3,100 | 3,100 |  |  |
Foreign |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |
Tax benefit primarily consisting of valuation allowances | 21,600 | 21,600 | $ 22,300 |  |
Net operating loss carry forwards which expire at various dates | 14,700 | 14,700 |  |  |
Net operating loss carryforwards | 165,500 | 165,500 |  |  |
Net operating loss carry forwards which have no expiration date | 150,800 | 150,800 |  |  |
Capital loss carryforwards | 21,500 | 21,500 |  |  |
Research and development credits | 3,900 | 3,900 |  |  |
State |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |
Net operating loss carry forwards which expire at various dates | $ 43,700 | $ 43,700 |  |  |

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