Goodwill and Intangible Assets - Summary of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2020	Oct. 31, 2019
Goodwill [Roll Forward]
Beginning Balance	$ 3,171,179	$ 3,143,249
Additions	173,732	23,690
Adjustments	59
Effect of foreign currency translation	20,144	4,240
Ending balance	3,365,114	3,171,179
Semiconductor And System Design
Goodwill [Roll Forward]
Beginning Balance	2,758,926	2,730,990
Additions	160,447	23,690
Adjustments	59
Effect of foreign currency translation	20,080	4,246
Ending balance	2,939,512	2,758,926
Software Integrity
Goodwill [Roll Forward]
Beginning Balance	412,253	412,259
Additions	13,285	0
Adjustments	0
Effect of foreign currency translation	64	(6)
Ending balance	$ 425,602	$ 412,253