Quarterly Financial Data (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 29, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jul. 01, 2012	Apr. 01, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Quarterly Financial Data [Abstract]
Net revenue	$ 356,620	$ 361,895	$ 357,719	$ 293,399	$ 310,436	$ 315,210	$ 320,655	$ 325,620	$ 1,369,633	$ 1,271,921	$ 1,181,018
Gross Profit	100,789	101,659	103,430	87,737	91,378	97,688	94,638	99,849	393,615	383,553	369,446
Provision for income taxes	11,712	10,364	7,144	8,545	12,325	9,920	9,933	10,565	37,765	42,743	32,842
Net Income	$ 11,432	$ 14,457	$ 13,985	$ 15,343	$ 16,079	$ 23,791	$ 21,522	$ 25,147	$ 55,217	$ 86,539	$ 91,368
Basic net income per share (in dollars per share)	$ 0.30	$ 0.37	$ 0.36	$ 0.40	$ 0.42	$ 0.62	$ 0.57	$ 0.67	$ 1.44	$ 2.27	$ 2.46
Diluted net income per share (in dollars per share)	$ 0.30	$ 0.37	$ 0.36	$ 0.39	$ 0.41	$ 0.61	$ 0.56	$ 0.65	$ 1.42	$ 2.23	$ 2.41