Revenue Recognition (Schedule of Disaggregation of Revenue) (Details) $ in Thousands	3 Months Ended
Dec. 29, 2023 USD ($) country	Dec. 30, 2022 USD ($)
Revenue from External Customer [Line Items]
Revenue from contract with customer	$ 315,574	$ 334,921
Revenue from contract with customer, percent	100.00%	100.00%
Countries technologies are licensed in \| country	70
United States
Revenue from External Customer [Line Items]
Revenue from contract with customer	$ 115,185	$ 100,262
Revenue from contract with customer, percent	37.00%	30.00%
International
Revenue from External Customer [Line Items]
Revenue from contract with customer	$ 200,389	$ 234,659
Revenue from contract with customer, percent	63.00%	70.00%
Licensing
Revenue from External Customer [Line Items]
Revenue from contract with customer	$ 293,767	$ 308,011
Revenue from contract with customer, percent	93.00%	92.00%
Revenue from contract with customer, licensing percent	100.00%	100.00%
Products and services
Revenue from External Customer [Line Items]
Revenue from contract with customer	$ 21,807	$ 26,910
Revenue from contract with customer, percent	7.00%	8.00%
Broadcast
Revenue from External Customer [Line Items]
Revenue from contract with customer	$ 112,416	$ 117,334
Revenue from contract with customer, licensing percent	38.00%	38.00%
Mobile
Revenue from External Customer [Line Items]
Revenue from contract with customer	$ 35,287	$ 64,286
Revenue from contract with customer, licensing percent	12.00%	21.00%
CE
Revenue from External Customer [Line Items]
Revenue from contract with customer	$ 53,220	$ 55,083
Revenue from contract with customer, licensing percent	18.00%	18.00%
PC
Revenue from External Customer [Line Items]
Revenue from contract with customer	$ 29,679	$ 24,286
Revenue from contract with customer, licensing percent	10.00%	8.00%
Other
Revenue from External Customer [Line Items]
Revenue from contract with customer	$ 63,165	$ 47,022
Revenue from contract with customer, licensing percent	22.00%	15.00%