Net Income (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	6 Months Ended
Jun. 26, 2020	Jun. 28, 2019	Jun. 26, 2020	Jun. 28, 2019
Numerator:
Net loss	$ (15,401)	$ (11,845)	$ (37,355)	$ (23,151)
Denominator:
Basic and diluted	96,727	88,931	96,255	88,554
Net loss per share:
Basic and diluted	$ (0.16)	$ (0.13)	$ (0.39)	$ (0.26)

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

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