Selected Quarterly Financial Data (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Oct. 01, 2013	Jul. 02, 2013	Apr. 02, 2013	Jan. 01, 2013	Oct. 02, 2012	Jul. 03, 2012	Apr. 03, 2012	Dec. 31, 2013	Jan. 01, 2013	Jan. 03, 2012
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 91,468	$ 88,936	$ 89,239	$ 81,280	$ 77,929	$ 77,099	$ 75,494	$ 69,888	$ 350,924	$ 300,410	$ 256,066
Operating income	5,163	5,580	937	2,572	3,369	4,004	5,199	3,481	14,252	16,052	12,016
Net income	$ 2,407	$ 3,265	$ 68	$ 924	$ 1,559	$ 133	$ 2,180	$ 1,291	$ 6,665	$ 5,163	$ 3,829
Basic EPS (USD per share)	$ 0.09	$ 0.11	$ 0.01	$ 0.04	$ 0.07	$ 0.01	$ 0.09	$ 0.06	$ 0.25	$ 0.22	$ 0.16
Diluted EPS (USD per share)	$ 0.08	$ 0.11	$ 0.01	$ 0.04	$ 0.07	$ 0.01	$ 0.09	$ 0.06	$ 0.24	$ 0.22	$ 0.16