Employee Stock Purchase and Stock Option Plans (Fair Value of Shares Vested) (Details) - Restricted Stock Units (RSUs) - USD ($) $ in Thousands	12 Months Ended
Sep. 27, 2019	Sep. 28, 2018	Sep. 29, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares vested	$ 54,988	$ 66,747	$ 38,649
Service Condition
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares vested	37,864	64,121	34,466
Service Market And Performance Conditions at Target
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares vested	17,124	$ 2,626	$ 4,183
1999 SIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of awards not yet recognized	$ 77,200
Exercisable options outstanding, weighted average remaining contractual life (years)	2 years 1 month 6 days

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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 (i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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+ References

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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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