Employee Stock Purchase and Stock Incentive Plans (Number of Shares of Restricted Stock and Restricted Stock Units Issued Under the 1999 Plans) (Details) - shares	12 Months Ended
Oct. 02, 2020	Sep. 27, 2019	Sep. 28, 2018
1999 ODSP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award number of shares, non-fungible share basis (in shares)	1.92
1999 ODSP \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock and restricted stock units outstanding (in shares)	34,000
1999 ODSP \| Restricted Stock Units (RSUs) \| Service Condition
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock and restricted stock units issued (in shares)	18,100	26,372	21,620
Restricted stock and restricted stock units outstanding (in shares)	88,210
1999 SIP \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock and restricted stock units issued (in shares)	0	0	0
Restricted stock and restricted stock units canceled (in shares)	34,417	105,301	284,254
Restricted stock and restricted stock units outstanding (in shares)	0
1999 SIP \| Restricted Stock Units (RSUs) \| Service Condition
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock and restricted stock units issued (in shares)	351,670	318,056	1,087,724
Restricted stock and restricted stock units canceled (in shares)	183,099	295,122	336,516
Restricted stock and restricted stock units outstanding (in shares)	756,054
1999 SIP \| Restricted Stock Units (RSUs) \| Service Market And Performance Conditions at Target
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock and restricted stock units issued (in shares)	202,792	240,068	254,784
Restricted stock and restricted stock units canceled (in shares)	160,781	183,654	95,063
Restricted stock and restricted stock units outstanding (in shares)	647,262

Share-based compensation arrangement by share-based payment award, award number of shares, non-fungible share basis.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ 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 (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ 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 (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

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.

+ 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 (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

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