Significant Accounting Policies - Revenues in Consolidated Statements of Operations (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2013	Oct. 31, 2012	Jul. 31, 2012	Apr. 30, 2012	Jan. 31, 2012	Oct. 31, 2013	Oct. 31, 2012	Oct. 31, 2011
Accounting Policies [Abstract]
Product sales, net									$ 1,801,355	$ 1,929,086	$ 1,898,731
Royalty income									9,215	12,763	17,596
Revenues, net	$ 475,913	$ 475,164	$ 447,304	$ 412,189	$ 529,230	$ 495,265	$ 482,652	$ 434,702	$ 1,810,570	$ 1,941,849	$ 1,916,327