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Income Taxes - Narrative (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2025 | Dec. 29, 2024 | Sep. 28, 2025 | Sep. 29, 2024 | Oct. 01, 2023 | Oct. 02, 2022
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |
Effective tax rate |  |  | 34.30% | 28.10% | 31.80% |
Impairment of goodwill | $ 0 |  | $ 92,416 | $ 0 | $ 0 |
Nondeductible expense, impairment losses, amount |  |  | 58,300 |  |  |
Legal fees |  | $ 115,000 | 115,000 | 0 | 0 |
Nondeductible expense, legal contingency charge, amount |  |  | 31,300 |  |  |
Non-operating income tax expense |  |  |  | 4,200 | 20,600 |
Reduction in tax expense (benefit), share-based payment arrangement, amount |  |  | $ 1,600 | $ 4,500 | $ 4,600 |
Effective tax rates, excluding valuation allowance release, non-deductible goodwill impairment charge, transaction costs, and excess tax benefits on share-based payments |  |  | 27.40% | 28.10% | 27.80% |
Valuation allowance |  |  | $ 17,791 | $ 16,841 |  |
Unrecognized tax benefits |  |  | 40,859 | 41,440 | $ 53,619 | $ 8,908
Accrual of additional interest and penalties |  |  | 3,400 | 3,800 | 4,600 |
Reduction in accrued interest and penalties |  |  |  | 3,200 | 2,000 |
Amount of interest and penalties accrued |  |  | 12,000 | $ 8,600 | $ 8,000 |
State |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |
Net operating loss carryforwards |  |  | 25,300 |  |  |
Net operating loss carry forwards which expire at various dates |  |  | 24,700 |  |  |
Net operating loss carry forwards which have no expiration date |  |  | 600 |  |  |
Foreign |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |
Net operating loss carryforwards |  |  | 71,100 |  |  |
Net operating loss carry forwards which expire at various dates |  |  | 12,700 |  |  |
Net operating loss carry forwards which have no expiration date |  |  | 58,400 |  |  |
Capital loss carryforwards |  |  | 40,400 |  |  |
Interest restriction allowances |  |  | $ 4,400 |  |  |

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