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, 2020
Jul. 31, 2019
Jul. 31, 2020
Jul. 31, 2019
Numerator:        
Net income $ 252,911 $ 99,929 $ 466,892 $ 371,653
Denominator:        
Weighted-average common shares for basic net income per share (shares) 151,352 150,123 150,731 149,708
Dilutive effect of potential common shares from equity-based compensation (shares) 4,621 4,477 4,343 4,151
Weighted-average common shares for diluted net income per share (shares) 155,973 154,600 155,074 153,859
Net income per share:        
Basic (in USD per share) $ 1.67 $ 0.67 $ 3.10 $ 2.48
Diluted (in USD per share) $ 1.62 $ 0.65 $ 3.01 $ 2.42
Anti-dilutive employee stock-based awards excluded (shares) [1] 3 152 610 798
[1]
These stock options and unvested restricted stock units were anti-dilutive for the respective periods and are excluded in calculating diluted net income per share. While such awards were anti-dilutive for the respective periods, they could be dilutive in the future.