Goodwill and Acquisition-Related Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 28, 2019	Mar. 30, 2019
Gross and net amounts of goodwill and of acquisition-related intangibles
Goodwill	$ 619,196	$ 340,718
Total acquisition-related intangibles, gross	361,881	210,976
Less accumulated amortization	(151,440)	(130,253)
Acquisition-related intangibles, net	210,441	80,723
Total	153,450
Core Technology [Member]
Gross and net amounts of goodwill and of acquisition-related intangibles
Total acquisition-related intangibles, gross	209,131	107,250
Less accumulated amortization	(98,310)	(82,611)
Total	$ 110,821	24,639
Weighted-Average Amortization Life	4 years 2 months 12 days
Other Intangibles [Member]
Gross and net amounts of goodwill and of acquisition-related intangibles
Total acquisition-related intangibles, gross	$ 95,759	51,016
Less accumulated amortization	(53,130)	(47,642)
Total	$ 42,629	3,374
Weighted-Average Amortization Life	4 years 1 month 6 days
In-process research and development
Gross and net amounts of goodwill and of acquisition-related intangibles
In-process research and development	$ 56,991	$ 52,710

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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