Income Taxes (Components Of Provision For Income Taxes) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Taxes [Abstract]
Current tax provision, Federal		$ 123,406	$ 86,002	$ 55,104
Current tax provision, State		28,657	21,803	14,900
Current tax provision, Foreign		(70)
Total current		151,993	107,805	70,004
Deferred tax provision, Federal		(14,008)	(1,615)	6,568
Deferred tax provision, State		(4,589)	653	(240)
Total deferred		(18,597)	(962)	6,328
Provision for income taxes	$ 21,616	$ 133,396	$ 106,843	$ 76,332