Quarterly Financial Data (Summary Of Unaudited Quarterly Financial Information) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Jan. 01, 2016	Oct. 02, 2015	Jul. 03, 2015	Apr. 03, 2015	Jan. 02, 2015	Oct. 03, 2014	Jul. 04, 2014	Apr. 04, 2014	Jan. 01, 2016	Jan. 02, 2015	Jan. 03, 2014
Quarterly Financial Data [Abstract]
Revenue	$ 126,626	$ 128,396	$ 132,441	$ 134,153	$ 131,126	$ 143,612	$ 147,761	$ 140,056
Gross Profit	$ 72,919	$ 76,058	$ 78,493	$ 80,326	$ 78,193	$ 83,849	$ 85,808	$ 78,905	$ 307,796	$ 326,755	$ 316,607
Income (loss) per share (basic):	$ 0.16	$ 0.13	$ 0.29	$ (0.53)	$ 0.13	$ 0.11	$ 0.11	$ 0.08	$ 0.05	$ 0.42	$ 0.02
Income (loss) per share (diluted):	$ 0.16	$ 0.13	$ 0.28	$ (0.53)	$ 0.13	$ 0.10	$ 0.10	$ 0.08	$ 0.05	$ 0.41	$ 0.02
Net (loss) income	$ 21,302	$ 16,984	$ 37,724	$ (68,824)	$ 17,274	$ 13,887	$ 13,646	$ 10,005