Segment Disclosure - Schedule of Segment Reporting Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Segment Reporting Information [Line Items]
Total revenue	$ 964,134	$ 852,970	$ 2,659,842	$ 2,509,613
Adjusted operating income	210,598	127,594	424,009	390,510
Operating Segments
Segment Reporting Information [Line Items]
Adjusted operating income	$ 323,553	$ 216,581	$ 731,890	$ 627,369
Adjusted operating margin	34.00%	25.00%	28.00%	25.00%
Operating Segments | Semiconductor & System Design:
Segment Reporting Information [Line Items]
Total revenue	$ 870,734	$ 769,411	$ 2,392,542	$ 2,260,372
Adjusted operating income	$ 308,730	$ 207,773	$ 697,273	$ 604,497
Adjusted operating margin	35.00%	27.00%	29.00%	27.00%
Operating Segments | Software Integrity:
Segment Reporting Information [Line Items]
Total revenue	$ 93,400	$ 83,559	$ 267,300	$ 249,241
Adjusted operating income	$ 14,823	$ 8,808	$ 34,617	$ 22,872
Adjusted operating margin	16.00%	11.00%	13.00%	9.00%