Composition Of Certain Financial Statement Captions (Schedule Of Accounts Receivable) (Details) - USD ($) $ in Thousands	Jun. 26, 2020	Sep. 27, 2019
Composition Of Certain Financial Statement Captions [Abstract]
Trade accounts receivable	$ 179,406	$ 151,996
Accounts receivable related to patent administration program	82,372	46,894
Accounts receivable, gross	261,778	198,890
Less: allowance for doubtful accounts	(14,292)	(9,775)
Accounts receivable, net	247,486	189,115
Unbilled Receivables, Current	$ 76,900	$ 82,300

Accounts Receivable Related To Patent Administration Program

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Composition Of Certain Financial Statement Captions [Abstract]

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Trade Accounts Receivable

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Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount of allowance for credit loss on accounts receivable, classified as current.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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