401(k) and Profit-Sharing Plan (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
401(k) and Profit-Sharing Plan (Textual) [Abstract]
Employer contribution in profit sharing plan	$ 2.7	$ 1.5	$ 2.2
Employer contribution in profit sharing plan, percentage	3.00%