Components of Other Intangible Assets and Estimated Useful Lives (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
Business Acquisition [Line Items]
Total intangible assets, fair value	$ 310,500
Total intangible assets, estimated useful life, years	6 years 6 months
Developed technology | Litepoint Corporation
Business Acquisition [Line Items]
Total intangible assets, fair value	237,100
Total intangible assets, estimated useful life, years	6 years 4 months 24 days
Customer Relationships | Litepoint Corporation
Business Acquisition [Line Items]
Total intangible assets, fair value	53,700
Total intangible assets, estimated useful life, years	7 years
Trade Names | Litepoint Corporation
Business Acquisition [Line Items]
Total intangible assets, fair value	19,000
Total intangible assets, estimated useful life, years	7 years
Customer Backlog | Litepoint Corporation
Business Acquisition [Line Items]
Total intangible assets, fair value	$ 700
Total intangible assets, estimated useful life, years	3 months 18 days