Goodwill and Identified Intangible Assets - Amortization Expense for Identifiable Purchased Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jul. 01, 2016	Jun. 30, 2017	Jul. 01, 2016
Acquired Finite-Lived Intangible Assets [Line Items]
Included in cost of revenue	$ 1,295	$ 1,307	$ 2,590	$ 1,725
Included in operating expenses	780	4,232	1,554	6,597
Total amortization expense	$ 2,075	$ 5,539	$ 4,144	$ 8,322