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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. 29, 2017 | Sep. 30, 2016 | Oct. 02, 2015
Stock Option Plans 1999 SIP | Restricted Stock |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock and restricted stock units issued |  | 597,091 | 507,882
Award number of shares, non-fungible share basis (in shares) | 1 |  |
Restricted stock and restricted stock units cancelled | 365,481 | 512,903 | 326,480
Award number of shares, fungible share basis (in shares) | 1.92 |  |
Stock Option Plans 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 |  |
Stock Option Plans 1999 SIP | Restricted stock, fungible |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock and restricted stock units outstanding | 950,593 |  |
Stock Option Plans 1999 SIP | Service Condition | Restricted Stock Units (RSUs) |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock and restricted stock units issued | 496,951 | 183,131 | 126,635
Restricted stock and restricted stock units cancelled | 128,536 | 177,640 | 70,296
Stock Option Plans 1999 SIP | Service Condition | Restricted stock units, fungible |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock and restricted stock units outstanding | 766,759 |  |
Stock Option Plans 1999 SIP | Service, Market, And Performance Conditions | Restricted Stock Units (RSUs) |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock and restricted stock units issued | 237,058 | 372,794 | 219,965
Restricted stock and restricted stock units cancelled | 86,742 | 275,933 | 194,116
Stock Option Plans 1999 SIP | Service, Market, And Performance Conditions | Restricted stock units, fungible |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock and restricted stock units outstanding | 672,440 |  |
Stock Option Plans 1999 ODSP |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Award number of shares, non-fungible share basis (in shares) | 1 |  |
Stock Option Plans 1999 ODSP | Restricted stock, non fungible |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock and restricted stock units outstanding | 34,000 |  |
Stock Option Plans 1999 ODSP | Service Condition |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock and restricted stock units issued | 21,123 | 23,090 | 13,500
Stock Option Plans 1999 ODSP | Service Condition | Restricted stock units, non fungible |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock and restricted stock units outstanding | 90,595 |  |

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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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