Business Acquisitions (Detail) - USD ($) $ in Thousands	Nov. 30, 2016	Nov. 04, 2016	Jun. 30, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill			$ 920,364	$ 801,406
Point Grey Research, Inc. [Member]
Business Acquisition [Line Items]
Cash acquired		$ 2,994
Other tangible assets and liabilities, net		35,064
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent		2,438
Identifiable intangible assets		39,800
Goodwill		183,741
Total purchase price		$ 259,161
Prox Dynamics, AS [Member]
Business Acquisition [Line Items]
Cash acquired			11,706
Other tangible assets and liabilities, net			(900)
Identifiable intangible assets	$ 31,400		31,400
Goodwill	91,900
Total purchase price	134,088
Prox Dynamics [Member]
Business Acquisition [Line Items]
Net deferred taxes			(7,400)
Goodwill			$ 99,300
Total purchase price	$ 134,088