Summary of Estimated Fair Values of Net Assets Acquired (Detail) - USD ($) $ in Thousands	Dec. 01, 2017	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill		$ 2,278,512	$ 2,016,169
Ruckus Wireless and ICX Switch business (Ruckus Networks)
Business Acquisition [Line Items]
Total estimated consideration transferred	$ 761,013
Cash and cash equivalents	18,958
Accounts receivables	32,940
Inventories	48,897
Prepaids and other	4,836
Property, plant & equipment	33,500
Intangible assets	472,500	472,500
Other assets	39,528
Accounts payable and accrued liabilities	(17,216)
Other current liabilities	(9,666)
Deferred revenue	(47,718)
Noncurrent deferred income tax liabilities, net	(92,233)
Other noncurrent liabilities	(41,347)
Net assets acquired	442,979
Goodwill	$ 318,034	$ 318,034