Segment Disclosure - Schedule of Segment Reporting Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019
Segment Reporting Information [Line Items]
Total revenue	$ 861,327	$ 836,242	$ 1,695,708	$ 1,656,643
Adjusted operating income	125,895	115,502	213,411	262,916
Operating Segments
Segment Reporting Information [Line Items]
Adjusted operating income	$ 221,404	$ 209,836	$ 408,337	$ 410,788
Adjusted operating margin	26.00%	25.00%	24.00%	25.00%
Operating Segments | Semiconductor & System Design:
Segment Reporting Information [Line Items]
Total revenue	$ 773,065	$ 753,055	$ 1,521,809	$ 1,490,961
Adjusted operating income	$ 209,692	$ 201,406	$ 388,543	$ 396,724
Adjusted operating margin	27.00%	27.00%	26.00%	27.00%
Operating Segments | Software Integrity:
Segment Reporting Information [Line Items]
Total revenue	$ 88,262	$ 83,187	$ 173,899	$ 165,682
Adjusted operating income	$ 11,712	$ 8,430	$ 19,794	$ 14,064
Adjusted operating margin	13.00%	10.00%	11.00%	8.00%