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Summary Of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 26, 2025 | Sep. 27, 2024 | Sep. 29, 2023
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Maximum credit exposure (percent) |  | 5.00% |  |  |
Advertising expense |  | $ 51,021 |  | $ 57,338 | $ 59,821
Transaction and re-measurement gains/losses |  | 1,252 |  | 1,800 | $ 536
Operating lease right-of-use assets |  | 33,204 |  | 39,046 |
Operating lease liabilities |  | 38,878 |  |  |
Other Comprehensive Income (Loss), before Reclassifications, before Tax |  | (897) |  | (1,035) |
Realized gains/(losses) | [1] | (543) |  | (2,302) |
Cash Flow Hedges |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Other Comprehensive Income (Loss), before Reclassifications, before Tax |  | (952) |  | 1,567 |
Realized gains/(losses) |  | $ (405) | [1] | $ (2,108) |
Minimum [Member] |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Intangible assets with definite lives, useful life, minimum years |  | 3 years |  |  |
Minimum [Member] | Internal Use Software [Member] |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Intangible assets with definite lives, useful life, minimum years |  | 3 years |  |  |
Maximum [Member] |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Intangible assets with definite lives, useful life, minimum years |  | 18 years |  |  |
Foreign Exchange Forward [Member] |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Derivative, Remaining Maturity |  |  |  | 31 days |
Notional amount of derivative |  | $ 110,100 |  | $ 106,300 |
Foreign Exchange Forward [Member] | Cash Flow Hedges |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Derivative, notional amount |  | $ 85,800 |  | $ 5,500 |
[1] | Realized gains or losses, if any, from the sale of our AFS investment securities or from foreign currency translation adjustments are included within other income/(expense), net in our consolidated statements of operations

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