Summary of Significant Accounting Policies Summary of Signicant Accounting Policies (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Shipping, Handling and Transportation Costs	$ 78,666	$ 61,423	$ 54,006
Amortization of stock-based compensation	$ 39,225	$ 34,613	$ 33,017