Acquisitions - Schedule of Estimated Contingent Consideration (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2024	Jul. 02, 2023	Jun. 30, 2024	Jul. 02, 2023
All acquisitions
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Aggregate maximum of contingent consideration	$ 128,573	$ 120,320	$ 128,573	$ 120,320
Contingent Consideration
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	74,579	88,082	73,422	65,566
Estimated earn-out liabilities for acquisitions	1,138	0	23,038	12,248
Payments of contingent consideration	(7,000)	(13,078)	(29,112)	(15,078)
Adjustments to fair value recorded in earnings	500	0	477	8,477
Interest accretion expense	1,038	707	1,953	1,919
Effect of foreign currency exchange rate changes	28	888	505	3,467
Ending balance	$ 70,283	$ 76,599	$ 70,283	$ 76,599

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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