Stockholders' Equity - Stock Options Outstanding, Exercisable and Expected to Vest (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015	Dec. 28, 2013
Stock options outstanding, exercisable and expected to vest
Options outstanding, Number of Shares	470,985	551,492	833,795	1,102,842
Options outstanding, Weighted Average Exercise Price	$ 8.69	$ 6.92	$ 4.88	$ 3.97
Options outstanding, Weighted Average Remaining Contractual Life (years)	4 years 6 months 29 days
Options outstanding, Aggregate Intrinsic Value	$ 2,611
Options vested and expected to vest, Number of Shares	436,564
Options vested and expected to vest, Weighted Average Exercise Price	$ 8.48
Options vested and expected to vest, Weighted Average Remaining Contractual Life (years)	4 years 5 months 23 days
Options vested and expected to vest, Aggregate Intrinsic Value	$ 2,505
Options exercisable, Number of Shares	236,399
Options exercisable, Weighted Average Exercise Price	$ 6.77
Options exercisable, Weighted Average Remaining Contractual Life (years)	3 years 7 months 28 days
Options exercisable, Aggregate Intrinsic Value	$ 1,725