Stock Based Compensation - Summary of Stock Options Outstanding, Vested and Expected to Vest and Exercisable (Details) (USD $) In Thousands, except Share data, unless otherwise specified	6 Months Ended
	Jun. 28, 2014	Dec. 28, 2013
Stock options outstanding, exercisable and expected to vest
Options outstanding, Number of Shares	995,036	1,102,842
Options vested and expected to vest, Number of Shares	926,071
Options exercisable, Number of Shares	564,581
Options outstanding, Weighted Average Exercise Price	$ 4.50	$ 3.97
Options vested and expected to vest, Weighted Average Exercise Price	$ 4.38
Options exercisable, Weighted Average Exercise Price	$ 3.58
Options outstanding, Weighted Average Remaining Contractual Life (years)	4 years 11 days
Options vested and expected to vest, Weighted Average Remaining Contractual Life (years)	3 years 10 months 17 days
Options exercisable, Weighted Average Remaining Contractual Life (years)	2 years 8 months 9 days
Options outstanding, Aggregate Intrinsic Value	$ 3,821
Options vested and expected to vest, Aggregate Intrinsic Value	3,662
Options exercisable, Aggregate Intrinsic Value	$ 2,655