Purchased Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Finite Lived Intangible Assets [Line Items]
Gross Assets	$ 51,593	$ 51,884
Accumulated Amortization	(38,637)	(36,879)
Net Assets	12,956	15,005
Technology and Patents
Finite Lived Intangible Assets [Line Items]
Gross Assets	34,290	34,524
Accumulated Amortization	(27,061)	(25,931)
Net Assets	7,229	8,593
Customer Relationships
Finite Lived Intangible Assets [Line Items]
Gross Assets	14,980	15,004
Accumulated Amortization	(10,351)	(9,732)
Net Assets	4,629	5,272
Leasehold Interest
Finite Lived Intangible Assets [Line Items]
Gross Assets	1,373	1,406
Accumulated Amortization	(275)	(266)
Net Assets	1,098	1,140
Non-compete agreements
Finite Lived Intangible Assets [Line Items]
Gross Assets	950	950
Accumulated Amortization	$ (950)	$ (950)