Employee Stock Purchase and Stock Option Plans (Number of Shares of Restricted Stock and Restricted Stock Units Issued Under the 1999 Plans) (Details) - shares	12 Months Ended
Sep. 27, 2019	Sep. 28, 2018	Sep. 29, 2017
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)	26,372	21,620	21,123
Restricted stock and restricted stock units outstanding (in shares)	92,068
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)	105,301	284,254	365,481
Restricted stock and restricted stock units outstanding (in shares)	95,626
1999 SIP \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award number of shares, non-fungible share basis (in shares)	1
Award number of shares, fungible share basis (in shares)	1.92
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)	318,056	1,087,724	496,951
Restricted stock and restricted stock units canceled (in shares)	295,122	336,516	128,536
Restricted stock and restricted stock units outstanding (in shares)	833,091
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)	240,068	254,784	237,058
Restricted stock and restricted stock units canceled (in shares)	183,654	95,063	86,742
Restricted stock and restricted stock units outstanding (in shares)	668,252

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

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- Definition

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

+ References

No definition available.

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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=116856206&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=116856206&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=116856206&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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