Stock Based Compensation - Summary of Stock Options Outstanding, Vested and Expected to Vest and Exercisable (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
	Jul. 04, 2015	Jan. 03, 2015
Stock options outstanding, exercisable and expected to vest
Options outstanding, Number of Shares	743,955	833,795
Options vested and expected to vest, Number of Shares	699,259
Options exercisable, Number of Shares	384,668
Options outstanding, Weighted Average Exercise Price	$ 5.86	$ 4.88
Options vested and expected to vest, Weighted Average Exercise Price	5.72
Options exercisable, Weighted Average Exercise Price	$ 4.54
Options outstanding, Weighted Average Remaining Contractual Life (years)	4 years 5 months 5 days
Options vested and expected to vest, Weighted Average Remaining Contractual Life (years)	4 years 4 months 6 days
Options exercisable, Weighted Average Remaining Contractual Life (years)	3 years 5 months 23 days
Options outstanding, Aggregate Intrinsic Value	$ 2,048
Options vested and expected to vest, Aggregate Intrinsic Value	2,000
Options exercisable, Aggregate Intrinsic Value	$ 1,453