Revenue Recognition (Schedule of Disaggregation of Revenue) (Details) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 26, 2026 USD ($)	Jun. 27, 2025 USD ($)	Jun. 26, 2026 USD ($) country	Jun. 27, 2025 USD ($)
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Total revenue	$ 304,995	$ 315,546	$ 1,047,331	$ 1,042,106
Revenue from contract with customer, percent	100.00%	100.00%	100.00%	100.00%
Countries technologies are licensed in \| country			60
United States
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Total revenue	$ 104,207	$ 89,825	$ 453,469	$ 392,319
Revenue from contract with customer, percent	34.00%	28.00%	43.00%	38.00%
International
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Total revenue	$ 200,788	$ 225,721	$ 593,862	$ 649,787
Revenue from contract with customer, percent	66.00%	72.00%	57.00%	62.00%
Licensing
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Total revenue	$ 282,351	$ 289,905	$ 974,367	$ 966,390
Revenue from contract with customer, percent	93.00%	92.00%	93.00%	93.00%
Revenue from contract with customer, licensing percent	100.00%	100.00%	100.00%	100.00%
Products and services
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Total revenue	$ 22,644	$ 25,641	$ 72,964	$ 75,716
Revenue from contract with customer, percent	7.00%	8.00%	7.00%	7.00%
Broadcast
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Total revenue	$ 106,579	$ 111,286	$ 326,041	$ 321,297
Revenue from contract with customer, licensing percent	38.00%	38.00%	33.00%	33.00%
Mobile
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Total revenue	$ 51,010	$ 56,295	$ 220,199	$ 217,942
Revenue from contract with customer, licensing percent	18.00%	19.00%	23.00%	23.00%
CE
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Total revenue	$ 31,506	$ 28,071	$ 118,057	$ 115,668
Revenue from contract with customer, licensing percent	11.00%	10.00%	12.00%	12.00%
PC
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Total revenue	$ 28,343	$ 33,589	$ 116,523	$ 123,247
Revenue from contract with customer, licensing percent	10.00%	12.00%	12.00%	13.00%
Other
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]
Total revenue	$ 64,913	$ 60,664	$ 193,547	$ 188,236
Revenue from contract with customer, licensing percent	23.00%	21.00%	20.00%	19.00%

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