Fair Value - Changes in Assets and Liabilities with Inputs Classified within Level 3 of Fair Value (Detail) - USD ($) $ in Thousands	12 Months Ended
Oct. 02, 2020	Sep. 27, 2019	Sep. 28, 2018
Warrant liability
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 12,364	$ 13,129	$ 40,775
Net Realized/Unrealized Losses (Gains) Included in Earnings	12,948	(765)	(27,646)
Purchases and Issuances	0	0	0
Sales and Settlements	0	0	0
Ending balance	25,312	12,364	13,129
Contingent consideration
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 0	585	1,679
Net Realized/Unrealized Losses (Gains) Included in Earnings		65	(394)
Purchases and Issuances		0	0
Sales and Settlements		(650)	(700)
Ending balance		$ 0	$ 585

Fair value measurement with unobservable inputs reconciliation recurring basis liability purchases and issuances.

No definition available.

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- Definition

Fair value measurement with unobservable inputs reconciliation recurring basis liability sales and settlement.

+ References

No definition available.

+ Details

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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.

+ Details

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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