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Employee Stock Purchase and Stock Option Plans (Unvested Restricted Stock and Restricted Stock Units Roll Forward) (Details) - $ / shares	12 Months Ended
	Sep. 28, 2018	Sep. 29, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Granted (in dollars per share)	$ 0.00	$ 0.00	$ 12.80
Restricted Stock And Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Beginning balance outstanding (in shares)	2,514,387
Granted (in shares)	1,364,128
Vested (in shares)	(1,209,322)
Canceled (in shares)	(339,658)
Ending balance outstanding (in shares)	2,329,535	2,514,387
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Beginning balance outstanding (in dollars per share)	$ 49.62
Granted (in dollars per share)	65.64
Vested (in dollars per share)	55.19
Canceled (in dollars per share)	49.57
Ending balance outstanding (in dollars per share)	$ 56.11	$ 49.62

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Gross number of share options (or share units) granted during the period.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average grant-date fair value of non-vested options forfeited.

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