Earnings Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jul. 01, 2012	Jun. 30, 2013	Jul. 01, 2012
Earnings per share
Net (loss)/earnings	$ (11,335)	$ 3,301	$ (7,767)	$ 5,584
Basic earnings per share, Shares	33,589	34,022	33,556	34,064
Equity-based compensation plans, Shares		552		583
Diluted earnings per share, Shares	33,589	34,574	33,556	34,647
Basic earnings per share, Per Share Amount	$ (0.34)	$ 0.10	$ (0.23)	$ 0.16
Diluted earnings per share, Per Share Amount	$ (0.34)	$ 0.10	$ (0.23)	$ 0.16