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Acquisitions - Schedule of Estimated Contingent Consideration (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Mar. 31, 2024 | Apr. 02, 2023 | Mar. 31, 2024 | Apr. 02, 2023
All acquisitions |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Aggregate maximum of contingent consideration | $ 129,253 | $ 143,882 | $ 129,253 | $ 143,882
Contingent Consideration |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Beginning balance | 55,604 | 69,029 | 73,422 | 65,566
Estimated earn-out liabilities for acquisitions | 21,900 | 12,248 | 21,900 | 12,248
Payments of contingent consideration | (3,250) | (2,000) | (22,112) | (2,000)
Adjustments to fair value recorded in earnings | 14 | 7,544 | (22) | 8,477
Interest accretion expense | 444 | 697 | 915 | 1,212
Effect of foreign currency exchange rate changes | (133) | 564 | 476 | 2,579
Ending balance | $ 74,579 | $ 88,082 | $ 74,579 | $ 88,082

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