Acquisitions - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended				0 Months Ended	9 Months Ended		0 Months Ended		0 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013	Dec. 31, 2013	Oct. 09, 2013 Antenna	Sep. 30, 2014 Antenna	Oct. 09, 2013 Antenna	Jul. 01, 2014 Profeatable	Jul. 01, 2014 Profeatable	Apr. 28, 2014 MeshLabs
Business Acquisition [Line Items]
Purchase price of acquired company							$ 27,100,000	$ 27,141,000		$ 2,300,000		$ 800,000
Cash acquired from acquisition										200,000
Consideration payable based on the achievement of certain performance milestones											1,100,000
Cash purchase price deposited in escrow									4,200,000
Acquisition-related costs	54,000	545,000	417,000		545,000			300,000
Purchase price adjustment against goodwill			6,006,000	[1]				6,000,000
Goodwill	45,009,000		45,009,000			43,469,000		23,018,000
Deferred tax assets								37,200,000
Deferred tax assets, valuation allowance								27,700,000
Deferred tax liability								6,900,000
Deferred tax assets, net								2,638,000
Acquired identifiable intangibles	$ 10,355,000		$ 10,355,000					$ 10,355,000

[1] The purchase price adjustments identified during the nine months of 2014 have been retroactively applied as of December 31, 2013.