Composition Of Certain Financial Statement Captions (Schedule Of Accrued Liabilities) (Details) - USD ($) $ in Thousands	Mar. 27, 2020	Sep. 27, 2019
Composition Of Certain Financial Statement Captions [Abstract]
Accrued royalties	$ 2,947	$ 2,957
Amounts payable to patent administration program partners	76,055	58,899
Accrued compensation and benefits	67,022	78,716
Accrued professional fees	16,600	19,216
Unpaid PP&E additions	9,820	15,332
Accrued customer refunds	15,751	24,299
Other accrued liabilities	57,674	68,725
Total	$ 245,869	$ 268,144

Accrual for Unpaid, Property, Plant and Equipment Additions

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Amounts Payable To Joint Licensing Program Partners

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Composition Of Certain Financial Statement Captions [Abstract]

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Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for royalties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer.

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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