Goodwill and Identified Intangible Assets - Estimated Future Amortization Expense of Purchased Intangible Assets (Detail) - USD ($) $ in Thousands	Mar. 30, 2018	Dec. 31, 2017
Acquired Finite-Lived Intangible Assets [Line Items]
2018 (remaining 9 months)	$ 6,298
2019	8,397
2020	4,029
2021	509
Total future amortization expense	19,233	$ 21,279
Cost of Sales [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
2018 (remaining 9 months)	3,885
2019	5,180
2020	951
2021	0
Total future amortization expense	10,016
Operating Expense [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
2018 (remaining 9 months)	2,413
2019	3,217
2020	3,078
2021	509
Total future amortization expense	$ 9,217