Stock Repurchase Program - Stock Repurchase Activities (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2017	Apr. 30, 2016
Stock Repurchase Program
Shares repurchased (in shares)	1,381	515	2,775	4,364
Total cost of the repurchased shares	$ 100,000	$ 20,000	$ 180,000	$ 200,000
Reissuance of treasury stock (in shares)	1,502	1,261	1,870	1,462