Stockholders' Equity And Stock-Based Compensation (Schedule Of Stock-Based Compensation Expense By Plan) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 24, 2021	Sep. 25, 2020	Sep. 27, 2019
Stockholders' Equity And Stock-Based Compensation [Line Items]
Allocated Share-based Compensation Expense	$ 99,698	$ 86,628	$ 76,580
Share based compensation expense	99,698	86,628	76,580
Benefit from income taxes	(15,790)	(14,090)	(12,884)
Recognized tax benefit from the exercise of ISO and ESPP	1,200
Allocated Share-based Compensation Expense, Net of Tax	83,908	72,538	63,696
Stock Option [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share based compensation expense	13,724	16,718	17,742
Restricted Stock Units [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share based compensation expense	80,705	65,235	54,650
Employee Stock Purchase Plan [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share based compensation expense	$ 5,269	$ 4,675	$ 4,188

Stockholders' Equity And Stock-Based Compensation [Line Items]

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of tax benefit from exercise of option under share-based payment arrangement.

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Amount of noncash expense for share-based payment arrangement.

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