Net Income Per Share - Computation of Basic and Diluted Net Income per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2016	Sep. 28, 2016	Jun. 29, 2016	Mar. 30, 2016	Dec. 30, 2015	Sep. 30, 2015	Jul. 01, 2015	Apr. 01, 2015	Dec. 28, 2016	Dec. 30, 2015	Dec. 31, 2014
Numerator:
Net income	$ 418	$ 5,211	$ 7,267	$ 5,443	$ 5,367	$ 4,666	$ 7,230	$ 6,791	$ 18,339	$ 24,054	$ 42,463
Denominator:
Weighted-average shares outstanding—Basic	38,437,020	38,415,189	38,294,575	38,284,435	38,284,435	38,275,317	37,812,767	37,424,745	38,357,805	37,949,316	32,285,484
Weighted-average shares outstanding—Diluted	39,108,967	39,083,577	38,962,802	39,001,078	38,965,248	39,107,241	39,085,206	38,921,884	39,026,950	39,039,558	34,346,241
Net income per share—Basic	$ 0.01	$ 0.14	$ 0.19	$ 0.14	$ 0.14	$ 0.12	$ 0.19	$ 0.18	$ 0.48	$ 0.63	$ 1.32
Net income per share—Diluted	$ 0.01	$ 0.13	$ 0.19	$ 0.14	$ 0.14	$ 0.12	$ 0.18	$ 0.17	$ 0.47	$ 0.62	$ 1.24
Anti-dilutive securities not considered in diluted EPS calculation									468,705	214,411	5,865