Schedule of Earnings Per Share, Basic and Diluted (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Basic EPS:
Net income (loss)	$ (12,665)	$ 22,184	$ 97,847	$ (524,512)
Weighted average common shares outstanding	50,825,000	50,177,000	50,562,000	50,114,000
Basic (in dollars per share)	$ (0.25)	$ 0.44	$ 1.94	$ (10.47)
Diluted EPS:
Net income (loss)	$ (12,665)	$ 22,184	$ 97,847	$ (524,512)
Weighted average common shares outstanding	50,825,000	50,177,000	50,562,000	50,114,000
Dilutive effect of stock awards (in shares)	0	1,000	11,000	0
Weighted average diluted shares outstanding	50,825,000	50,178,000	50,573,000	50,114,000
Diluted (in dollars per share)	$ (0.25)	$ 0.44	$ 1.93	$ (10.47)
Stock Compensation Plan
Stock Based Awards Additional Disclosure:
Antidilutive Stock Based Awards Excluded from Computation of Earnings Per Share	2,700,000	3,000,000	2,700,000	2,900,000