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Employee Stock Purchase and Stock Option Plans (Fair Value of Shares Vested) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 28, 2018	Sep. 29, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of awards not yet recognized	$ 93,300
Options Outstanding, Weighted Average Remaining Contractual Life (years)	4 years 3 months 18 days
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares vested	$ 66,747	$ 38,649	$ 21,817
Restricted Stock Units (RSUs) | Service Condition
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares vested	64,121	34,466	17,481
Restricted Stock Units (RSUs) | Service Market And Performance Conditions at Target
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares vested	$ 2,626	$ 4,183	$ 4,336

X

- Definition

Unrecognized cost of unvested share-based compensation awards.

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

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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

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+ References

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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