Net Income (Loss) Per Share - Basic and Diluted Net Income (loss) Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 24, 2016	Jun. 30, 2017	Jun. 24, 2016
Numerator:
Net income (loss)	$ 20,179	$ 723	$ 34,520	$ (2,516)
Shares used in computation — basic:
Weighted average common shares outstanding	33,433	32,565	33,247	32,437
Shares used in computation — diluted:
Shares used in computing basic net income (loss) per share	33,433	32,565	33,247	32,437
Dilutive effect of common shares outstanding subject to repurchase	622	184	749
Dilutive effect of options outstanding	9	43	21
Weighted average shares used in computing diluted net income (loss) per share	34,064	32,792	34,017	32,437
Net income (loss) per share — basic	$ 0.60	$ 0.02	$ 1.04	$ (0.08)
Net income (loss) per share — diluted	$ 0.59	$ 0.02	$ 1.01	$ (0.08)