Stockholders' Equity - Stock Options Outstanding, Exercisable and Expected to Vest (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015
Stock options outstanding, exercisable and expected to vest
Options outstanding, Number of Shares	857,311	470,985	551,492	833,795
Options outstanding, Weighted Average Exercise Price	$ 9.49	$ 8.69	$ 6.92	$ 4.88
Options outstanding, Weighted Average Remaining Contractual Life (years)	5 years 3 months 29 days
Options outstanding, Aggregate Intrinsic Value	$ 278
Options vested and expected to vest, Number of Shares	773,545
Options vested and expected to vest, Weighted Average Exercise Price	$ 9.43
Options vested and expected to vest, Weighted Average Remaining Contractual Life (years)	5 years 2 months 19 days
Options vested and expected to vest, Aggregate Intrinsic Value	$ 278
Options exercisable, Number of Shares	289,836
Options exercisable, Weighted Average Exercise Price	$ 8.25
Options exercisable, Weighted Average Remaining Contractual Life (years)	3 years 7 months 24 days
Options exercisable, Aggregate Intrinsic Value	$ 272