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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
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Sep. 28, 2018 | Sep. 29, 2017 | Sep. 30, 2016
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 [Member] |  |  |
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) | 21,620 | 21,123 | 23,090
Restricted stock and restricted stock units outstanding (in shares) | 91,092 |  |
1999 SIP | Restricted Stock [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock and restricted stock units issued (in shares) | 0 | 0 | 597,091
Restricted stock and restricted stock units canceled (in shares) | 284,254 | 365,481 | 512,903
Award number of shares, fungible share basis (in shares) | 1.92 |  |
Restricted stock and restricted stock units outstanding (in shares) | 337,805 |  |
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) | 1,087,724 | 496,951 | 183,131
Restricted stock and restricted stock units canceled (in shares) | 336,516 | 128,536 | 177,640
Restricted stock and restricted stock units outstanding (in shares) | 1,131,200 |  |
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) | 254,784 | 237,058 | 372,794
Restricted stock and restricted stock units canceled (in shares) | 95,063 | 86,742 | 275,933
Restricted stock and restricted stock units outstanding (in shares) | 735,438 |  |

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- Definition Share-based compensation arrangement by share-based payment award, award number of shares, fungible share basis. + References No definition available. + Details
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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. + Details
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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://www.xbrl.org/2003/role/presentationRef -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=96867065&loc=d3e5070-113901 + Details
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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://www.xbrl.org/2003/role/presentationRef -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=96867065&loc=d3e5070-113901 + Details
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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://www.xbrl.org/2003/role/presentationRef -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=96867065&loc=d3e5070-113901 + Details
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