Business Acquisitions (Detail) - USD ($) $ in Thousands	Nov. 30, 2016	Nov. 04, 2016	Mar. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill			$ 896,436	$ 801,406
Point Grey Research, Inc. [Member]
Business Acquisition [Line Items]
Cash acquired		$ 2,994
Other tangible assets and liabilities, net		35,127
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent		2,438
Identifiable intangible assets		39,800
Goodwill		183,678
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
Goodwill	91,900
Total purchase price	$ 134,088