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

Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations.

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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

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Amount of gain (loss) recognized in other comprehensive income (OCI) from liability measured at fair value on recurring basis using unobservable input (level 3).

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Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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