Goodwill and Identified Intangible Assets - Estimated Future Amortization Expense of Purchased Intangible Assets (Detail) - USD ($) $ in Thousands	Mar. 27, 2020	Dec. 31, 2019
Acquired Finite-Lived Intangible Assets [Line Items]
2020 (remaining nine months)	$ 2,293
2021	496
Total future amortization expense	2,789	$ 4,461
Cost of Revenue [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
2020 (remaining nine months)	65
2021	0
Total future amortization expense	65
Operating Expense [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
2020 (remaining nine months)	2,228
2021	496
Total future amortization expense	$ 2,724