Summary of Significant Accounting Policies - Reconciliation of Weighted Average Common Shares Used to Calculate Basic Net Income Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2016
Earnings Per Share [Abstract]
Net income	$ 432,518	$ 136,563	$ 266,826
Weighted average common shares for basic net income per share (in shares)	149,036	150,457	152,017
Dilutive effect of common share equivalents from equity-based compensation (in shares)	4,357	4,417	2,704
Weighted average common shares for diluted net income per share (in shares)	153,393	154,874	154,721
Basic (in USD per share)	$ 2.90	$ 0.91	$ 1.76
Diluted (in USD per share)	$ 2.82	$ 0.88	$ 1.73
Anti-dilutive employee stock-based awards excluded (in shares)	850	345	1,971