Industry Segment, Geographic Information and Significant Customers - Segment Information about Revenue, Cost of Revenue, Gross Margin and Income before Income Taxes (Detail) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 26, 2020 USD ($)	Sep. 28, 2019 USD ($)	Sep. 26, 2020 USD ($) segment	Sep. 28, 2019 USD ($)
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Number of Reportable Segments \| segment			1
Total cost of revenue	$ 214,304	$ 152,558	$ 430,755	$ 412,675
Gross profit	198,841	136,841	454,808	374,557
Research and development	38,613	33,401	111,929	104,320
Selling and marketing	50,488	42,257	136,144	137,502
General and administrative	28,490	18,372	74,919	61,871
Other income, net	$ 42,240	$ 900	$ 41,837	$ 3,713
Amazon [Member] \| Customer Concentration Risk [Member] \| Revenue Benchmark [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Concentration Risk, Percentage	26.60%	29.60%	26.40%	25.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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