Amount of Assets and Liabilities of Nexus at Fair Value as of Acquisition Date (Detail) (Nexus, USD $) In Thousands, unless otherwise specified	Jul. 25, 2011
Business Acquisition [Line Items]
Accounts receivable	$ 5,708
Inventory	7,481
Other current assets	4,522
Property, plant and equipment	12,527
Goodwill	33,033
Accounts payable and accrued expenses	(6,563)
Deferred revenue	(3,692)
Other current liabilities	(1,534)
Deferred tax liabilities	(2,584)
Other long-term liabilities	(1,070)
Total purchase price, net of cash acquired	84,928
Completed technology
Business Acquisition [Line Items]
Identifiable intangible assets	6,000
Customer relationships
Business Acquisition [Line Items]
Identifiable intangible assets	31,000
Trademarks and trade names
Business Acquisition [Line Items]
Identifiable intangible assets	$ 100