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, 2017	Jul. 31, 2016	Jul. 31, 2017	Jul. 31, 2016
Numerator:
Net income	$ 116,751	$ 64,718	$ 256,645	$ 194,129
Denominator:
Weighted-average common shares for basic net income per share (shares)	150,214	151,169	150,460	152,129
Dilutive effect of potential common shares from equity-based compensation (shares)	4,469	2,721	4,327	2,500
Weighted-average common shares for diluted net income per share (shares)	154,683	153,890	154,787	154,629
Net income per share:
Basic (in USD per share)	$ 0.78	$ 0.43	$ 1.71	$ 1.28
Diluted (in USD per share)	$ 0.75	$ 0.42	$ 1.66	$ 1.26
Anti-dilutive employee stock-based awards excluded (shares)	492	2,270	1,186	1,822