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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. 27, 2019	Sep. 28, 2018	Sep. 29, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Granted (in dollars per share)	$ 0	$ 0	$ 0
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)	2,329,535
Granted (in shares)	710,718
Vested (in shares)	(1,093,926)
Canceled (in shares)	(223,290)
Ending balance outstanding (in shares)	1,723,037	2,329,535
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)	$ 56.11
Granted (in dollars per share)	73.12
Vested (in dollars per share)	51.54
Canceled (in dollars per share)	57.87
Ending balance outstanding (in dollars per share)	$ 65.80	$ 56.11

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- Definition

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

+ References

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

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

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