Earnings Per Share (Computations Of Basic And Diluted EPS) (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Earnings Per Share
Net income applicable to common shareholders	$ 46,016	$ 26,161	$ 113,186	$ (77,281)
Less: Undistributed net income allocable to participating securities	(549)	(356)	1,403
Net income per common share - Basic	45,467	25,805	111,783	(77,281)
Weighted average number of shares outstanding - basic	104,700	104,090	104,616	103,772
Stock options, Income
Stock options, Shares	93	22	84
Undistributed earnings reallocated to participating securities, value	2	5	6
Undistributed earnings reallocated to participating securities, shares
Convertible Senior Notes, Value
Convertible Senior Notes, Shares
Convertible preferred stock	10		30
Convertible preferred stock, Shares	361	1,195	361
Net income per common share - Diluted	$ 45,479	$ 25,810	$ 111,819	$ (77,281)
Weighted Average Number of Shares Outstanding, Diluted, Total	105,154	105,307	105,061	103,772