Acquisitions and Divestitures - Changes in the Carrying Value of Estimated Contingent Earn-Out Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 27, 2020	Sep. 27, 2020	Sep. 29, 2019	Sep. 30, 2018
Earn-out payments:
Reported as cash used in operating activities		$ 0	$ 0	$ (2,349)
Reported as cash used in financing activities		(22,900)	(12,018)	(1,412)
Contingent consideration
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance		52,992	35,290	2,438
Acquisition date fair value of contingent earn-out liabilities		16,581	27,704	32,210
Earnings adjustment to contingent earn-out liabilities	$ (13,500)
Foreign exchange impact		(247)	(558)	(854)
Earn-out payments:
Reported as cash used in operating activities		0	0	(2,349)
Reported as cash used in financing activities		(22,900)	(12,018)	(1,412)
Ending balance	$ 32,617	32,617	52,992	35,290
Interest expense \| Contingent consideration
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Earnings adjustment to contingent earn-out liabilities		1,162	1,489	1,005
Operating income \| Contingent consideration
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Earnings adjustment to contingent earn-out liabilities		$ (14,971)	$ 1,085	$ 4,252

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
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- Definition

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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-Publisher FASB
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- Definition

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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- Definition

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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- Definition

Amount of cash outflow, not made soon after acquisition date of business combination, to settle contingent consideration liability up to amount recognized at acquisition date, including, but not limited to, measurement period adjustment and less amount paid soon after acquisition date.

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Amount of cash outflow, not made soon after acquisition date of business combination, to settle contingent consideration liability exceeding amount recognized at acquisition date. Includes, but is not limited to, measurement period adjustment and less amount paid soon after acquisition date.

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