Acquisitions - Pro-Forma Information (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Business Combinations [Abstract]
Pro forma net sales	$ 1,332,176	$ 1,069,564
Pro forma net income (loss)	$ 7,033	$ (24,268)
Pro forma basic net income (loss) per share	$ 0.31	$ (1.06)
Pro forma diluted net income (loss) per share	$ 0.28	$ (1.06)