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Employee Stock Purchase and Stock Option Plans (Total Pre-Tax Compensation Cost Relating to Share-Based Payments Included in the Accompanying Consolidated Statements of Earnings) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 29, 2017 | Sep. 30, 2016 | Oct. 02, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] |  |  |
Share-based compensation expense (pre-tax) | $ 38,764 | $ 32,370 | $ 41,412

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