Income per Share (Details) (USD $) In Thousands, except Share data	3 Months Ended		6 Months Ended
	Jul. 03, 2011	Jul. 04, 2010	Jul. 03, 2011	Jul. 04, 2010
Numerator:
Income (loss) from continuing operations	$ 34,881	$ 21,585	$ 56,899	$ 35,915
Loss from discontinued operations, net of tax	(156)	(1,913)	(284)	(4,496)
Net income (loss)	$ 34,725	$ 19,672	$ 56,615	$ 31,419
Denominator:
Weighted average shares outstanding, basic	47,401,000	46,779,000	47,304,000	46,737,000
Effect of dilutive common stock equivalents	1,013,000	1,009,000	1,068,000	910,000
Weighted average shares outstanding, diluted	48,414,000	47,788,000	48,372,000	47,647,000
Income per Share (Textuals) [Abstract]
Number of outstanding equity awards not included in the diluted weighted average shares outstanding, because to do so would have been anti-dilutive	700,000	1,600,000	600,000	1,400,000