Income Taxes (Schedule Of Income Tax Expense (Benefit)) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Taxes [Abstract]
Federal, Current	$ (57)	$ (19,190)	$ (58,972)
State, Current	1,150	390	(3,327)
Total, Current	1,093	(18,800)	(62,299)
Federal, Deferred	27,940	(5,045)	(23,217)
State, Deferred	2,755	(948)	(2,013)
Total, Deferred	30,695	(5,993)	(25,230)
Income tax benefit (expense)	$ 31,788	$ (24,793)	$ (87,529)