Stock Repurchase Program - Additional Information (Detail) (USD $)	3 Months Ended
	Jan. 31, 2015	Dec. 31, 2014	Dec. 03, 2013
Stock Repurchase Program [Abstract]
Stock repurchase program authorized amount	$ 500,000,000.0		$ 500,000,000.0
Remaining amount available for further repurchases	200,300,000.0
Accelerated share repurchase amount		180,000,000.0
Prepayment amount	180,000,000.0
Value of initial share delivery	144,000,000
Average price paid (in dollars per share)	$ 43.77
Remaining repurchase amount	$ 36,000,000
Settlement period for remaining balance	6 months