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

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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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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