Income Taxes (Schedule Of Total Provision For Income Taxes) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Taxes [Abstract]
Current taxes, Federal	$ (3,159)	$ (6,856)	$ (5,124)
Current taxes, State	743	(3,079)	4,901
Current taxes	(2,416)	(9,935)	(223)
Deferred taxes, Federal	109,363	88,021	(23,510)
Deferred taxes, State	16,188	12,651	(8,493)
Deferred taxes	125,551	100,672	(32,003)
Total income taxes	$ 123,135	$ 90,737	$ (32,226)