Net Loss Per Share - Numerators and Denominators of Basic and Diluted Net Income (Loss) Per Share Computations (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 29, 2019	Mar. 30, 2018
Numerator:
Net loss	$ (11,306)	$ (13,694)
Denominator:
Basic and diluted	88,165	83,912
Net loss per share:
Basic and diluted	$ (0.13)	$ (0.16)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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