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Acquisitions - Summary of Estimated Contingent Consideration (Details) - Contingent Consideration - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 29, 2025 | Jun. 30, 2024 | Jun. 29, 2025 | Jun. 30, 2024
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Beginning balance | $ 31,270 | $ 74,579 | $ 48,746 | $ 73,422
Estimated earn-out liabilities for acquisitions | 37,977 | 1,138 | 43,493 | 23,038
Payments of contingent consideration | (360) | (7,000) | (22,225) | (29,112)
Adjustments to fair value recorded in earnings | (58) | 500 | (2,355) | 477
Interest accretion expense | 478 | 1,038 | 1,641 | 1,953
Effect of foreign currency exchange rate changes | 424 | 28 | 431 | 505
Ending balance | $ 69,731 | $ 70,283 | $ 69,731 | $ 70,283

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