Net Income Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 01, 2013	Oct. 02, 2012	Oct. 01, 2013	Oct. 02, 2012
Net Income Per Share
Shares of restricted stock issued to employees, unvested	1,600,000	1,200,000	1,600,000	1,200,000
Net income per share, basic and diluted
Net income	$ 27,481	$ 27,163	$ 81,356	$ 76,284
Basic weighted average shares outstanding	52,416,000	52,958,000	52,521,000	53,264,000
Dilutive effect of equity awards (in shares)	2,196,000	2,168,000	2,133,000	2,007,000
Diluted weighted average shares outstanding	54,612,000	55,126,000	54,654,000	55,271,000
Basic net income per share (in dollars per share)	$ 0.52	$ 0.51	$ 1.55	$ 1.43
Diluted net income per share (in dollars per share)	$ 0.50	$ 0.49	$ 1.49	$ 1.38
Shares of common stock not included in the diluted calculation due to their anti-dilutive effect	600,000	1,900,000	1,300,000	2,800,000