Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Sep. 28, 2018	Sep. 29, 2017
Intangible Assets By Major Class [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	$ 701,715	$ 731,132
Accumulated Amortization	436,025	413,378
Trademarks
Intangible Assets By Major Class [Line Items]
Indefinite-lived Intangible Assets, Gross Carrying Amount	40,395	41,412
Programs
Intangible Assets By Major Class [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	603,403	625,470
Accumulated Amortization	$ 361,317	339,920
Estimated amortization of intangible assets	16 years
Core Technology
Intangible Assets By Major Class [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	$ 9,977	15,926
Accumulated Amortization	$ 8,283	13,123
Estimated amortization of intangible assets	11 years
Patents and Other
Intangible Assets By Major Class [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	$ 88,335	89,736
Accumulated Amortization	$ 66,425	$ 60,335
Estimated amortization of intangible assets	12 years