Net Income per Share - Reconciliation of Weighted Average Common Shares Used to Calculate Basic Net Income Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Numerator:
Net income	$ 79,409	$ 116,751	$ 178,190	$ 256,645
Denominator:
Weighted-average common shares for basic net income per share (shares)	148,490	150,214	148,760	150,460
Dilutive effect of potential common shares from equity-based compensation (shares)	4,124	4,469	4,358	4,327
Weighted-average common shares for diluted net income per share (shares)	152,614	154,683	153,118	154,787
Net income per share:
Basic (in USD per share)	$ 0.53	$ 0.78	$ 1.20	$ 1.71
Diluted (in USD per share)	$ 0.52	$ 0.75	$ 1.16	$ 1.66
Anti-dilutive employee stock-based awards excluded (shares)	1,063	492	774	1,186