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Employee Stock Purchase and Stock Option Plans (Fair Value of Shares Vested) (Details) - Restricted Stock Units (RSUs) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 29, 2017 | Sep. 30, 2016 | Oct. 02, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Fair value of shares vested | $ 38,649 | $ 21,817 | $ 29,832
Service Condition |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Fair value of shares vested | 34,466 | 17,481 | 18,568
Service, Market, And Performance Conditions |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Fair value of shares vested | $ 4,183 | $ 4,336 | $ 11,264

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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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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. + Details
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