Consolidated Statements of Stockholders' Equity (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Unrealized loss on hedges, income tax benefit (provision)	$ 0	$ 386	$ 32,601
Reclassification adjustment for hedge gains (losses) included in net income (loss), income tax benefit (provision)	$ (10,580)	$ (10,729)	$ 8,095