Business Combination Pro Forma Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Jul. 31, 2012		Jul. 31, 2011		Jul. 31, 2012		Jul. 31, 2011
Business Acquisition [Line Items]
Revenue	$ 443,747	[1]	$ 422,101	[1]	$ 1,344,413	[1]	$ 1,253,219	[1]
Net Income	$ 75,656	[1]	$ 44,109	[1]	$ 153,854	[1],[2]	$ 130,988	[1],[2]

[1] Disclosure of the specific revenue contribution and net income of Magma subsequent to the acquisition, for the periods presented, is impracticable as the operations of Magma are integrated with the Company's operations and not separately tracked.

[2] 2012 supplemental pro forma net income was adjusted to exclude $32.7 million of acquisition-related costs during the nine months ended July 31, 2012. Corresponding periods of 2011 supplemental pro forma net income were adjusted to include these charges.