Composition Of Certain Financial Statement Captions (Schedule Of Accounts Receivable) (Details) - USD ($) $ in Thousands	Sep. 27, 2019	Sep. 28, 2018
Composition Of Certain Financial Statement Captions [Abstract]
Trade accounts receivable	$ 151,996	$ 108,929
Accounts receivable from patent administration program partners	46,894	62,462
Accounts receivable, gross	198,890	171,391
Less: allowance for doubtful accounts	(9,775)	(5,258)
Total	$ 189,115	$ 166,133

Accounts Receivable Related To Patent Administration Program

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- Definition

Composition Of Certain Financial Statement Captions [Abstract]

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- Definition

Trade Accounts Receivable

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- Definition

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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