Components of Intangible Assets Net (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011
Finite-Lived Intangible Assets
Gross Carrying Amount	$ 406,092		$ 402,262
Accumulated Amortization and Impairments	(279,249)		(251,876)
Net	126,843		150,386
Acquired Technology And IPR&D
Finite-Lived Intangible Assets
Gross Carrying Amount	247,181	[1]	244,680	[1]
Accumulated Amortization and Impairments	(172,458)	[1]	(157,944)	[1]
Net	74,723	[1]	86,736	[1]
Customer relationships
Finite-Lived Intangible Assets
Gross Carrying Amount	124,017		122,918
Accumulated Amortization and Impairments	(79,343)		(67,193)
Net	44,674		55,725
Non-compete agreements
Finite-Lived Intangible Assets
Gross Carrying Amount	15,298		15,068
Accumulated Amortization and Impairments	(14,230)		(13,896)
Net	1,068		1,172
Trademarks and trade names
Finite-Lived Intangible Assets
Gross Carrying Amount	19,596	[2]	19,596	[2]
Accumulated Amortization and Impairments	(13,218)	[2]	(12,843)	[2]
Net	$ 6,378	[2]	$ 6,753	[2]

[1] IPR&D projects were identified and valued related to our acquisitions. These projects are continually assessed for impairment. Upon completion, these projects will be amortized over their estimated useful life.

[2] Trademarks and trade names include $0.8 million in trade names related to our acquisition of PacketTrap that have an indefinite useful life, and as such are not being amortized.