Share-Based Compensation - Summary of Outstanding Share-Based Awards (Detail) - shares	Sep. 27, 2020	Sep. 29, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested options, outstanding	235,000	578,000
Unvested options, outstanding	1,095,000	64,000
RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based awards other than options, outstanding	914,000	774,000
PSAs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based awards other than options, outstanding	315,000	225,000
RSAs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based awards other than options, outstanding	0	55,000

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Number of non-vested options outstanding.

+ References

No definition available.

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