Segment Information (Reconciliation Statement Of Segment Income from Operations To Consolidated Income Before Income Taxes) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Segment Reporting [Abstract]
Income (loss) from operations	$ 135,960	$ 76,256	$ (398,943)	$ 273,848
Interest expense	(75,710)	(77,694)	(229,210)	(154,523)
Interest income	1,459	840	3,568	2,341
Other nonoperating expenses		(1,708)	(19,042)	(51,448)
Income (loss) before income taxes	$ 61,709	$ (2,306)	$ (643,627)	$ 70,218