Net Income Per Share - Basic and Diluted Net Income Per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 27, 2013	Dec. 28, 2012	Dec. 30, 2011
Numerator:
Net income	$ 10,424	$ 5,153	$ 23,734
Shares used in computation - basic:
Weighted average common shares outstanding	28,346	25,698	22,689
Shares used in computation - diluted:
Weighted average common shares outstanding	28,346	25,698	22,689
Dilutive effect of common shares outstanding subject to repurchase	456	244	241
Dilutive effect of options outstanding	235	319	507
Shares used in computing diluted net income per share	29,037	26,261	23,437
Net income per share - basic	$ 0.37	$ 0.20	$ 1.05
Net income per share - diluted	$ 0.36	$ 0.20	$ 1.01