Earnings Per Share (Computations of Basic and Diluted EPS) (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Net income (loss) applicable to common shareholders	$ 41,313	$ (85,551)	$ 67,170	$ (103,442)
Less: Undistributed net income allocable to participating securities	(514)	0	(850)
Net Income Loss Available To Common Stockholders Basic Net Of Distributions To Securities	40,799	(85,551)	66,320	(103,442)
Weighted average number of shares outstanding - basic	104,673	104,125	104,573	103,610
Stock options, Income	0	0	0	0
Stock options, Shares	106	0	90	0
Undistributed earnings reallocated to participating securities, value	3	0	4	0
Undistributed earnings reallocated to participating securities, shares	0	0	0	0
Convertible Senior Notes, Value	0	0	0	0
Convertible Senior Notes, Shares	0	0	0	0
Convertible preferred stock	10	0	20	0
Convertible preferred stock, Shares	361	0	361	0
Net income (loss) per common share - Diluted	40,812	(85,551)	66,344	(103,442)
Weighted Average Number of Shares Outstanding, Diluted, Total	105,140	104,125	105,024	103,610
Helix [Member]
Net income (loss) applicable to common shareholders	$ 41,292	$ (81,156)	$ 67,097	$ (95,128)

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