Stock-Based Compensation And Employee Benefit Plans (Schedule Of Stock Options Activity) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 years	Dec. 31, 2010	Dec. 31, 2009
Stock-Based Compensation And Employee Benefit Plans [Abstract]
Number of Options Outstanding at beginning of period	1,315,000
Number of Options granted	31,000
Number of Options exercised	(202,578)	(748,486)	(320,245)
Number of Options forfeited	(10,000)
Number of Options expired	0
Number of Options Outstanding at end of period	1,133,000	1,315,000
Number of Options Exercisable at end of period	860,000
Weighted Average Exercise Price Outstanding at beginning of period	$ 17.37
Weighted Average Exercise Price Options granted	$ 22.28
Weighted Average Exercise Price Options exercised	$ 14.51
Weighted Average Exercise Price Options forfeited	$ 17.08
Weighted Average Exercise Price Options expired	$ 0.00
Weighted Average Exercise Price Outstanding at end of period	$ 18.01	$ 17.37
Weighted Average Exercise Price Exercisable at end of period	$ 17.84
Weighted Average Remaining Contractual Term Outstanding at end of period, years	4.32
Weighted Average Remaining Contractual Term Exercisable at end of period, years	3.39
Aggregate Intrinsic Value Outstanding at end of period	$ 6,899
Aggregate Intrinsic Value Exercisable at end of period	$ 5,388