Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2025	Jul. 31, 2024	Jul. 31, 2025	Jul. 31, 2024	Jul. 17, 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense before taxes	$ 267,723	$ 181,539	$ 655,909	$ 540,026
Assumed Equity Awards | Ansys, Inc
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value					$ 639,700
Total stock-based compensation expense before taxes	67,200
Unrecognized stock-based compensation expense	432,500		$ 432,500
Weighted-average period of recognition for unrecognized stock-based compensation expense			1 year 8 months 26 days
Assumed Equity Awards, recognized as goodwill | Ansys, Inc
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value					131,000
Assumed Equity Awards, to be recognized as stock-based compensation expense | Ansys, Inc
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value					$ 508,700
Nonvested awards (in shares)					1.1
Estimated weighted average fair value (in USD per share)					$ 453.83
Options, Restricted Stock and Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense	1,700,000		$ 1,700,000
Weighted-average period of recognition for unrecognized stock-based compensation expense			2 years
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense	$ 109,200		$ 109,200
Weighted-average period of recognition for unrecognized stock-based compensation expense			2 years