Equity-Based Compensation (Summary Of Outstanding Stock Options) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at January 1, (in shares)	144,684	222,130	329,426
Shares exercised	(60,857)	(77,446)	(107,296)
Outstanding and exercisable at December 31, (in shares)	83,827	144,684	222,130
Outstanding at January 1, Weighted Avg. Exercise Price (in dollars per share)	$ 23.34	$ 21.64	$ 21.14
Shares exercised, Weighted Avg. Exercise Price (in dollars per share)	$ 17.66	$ 18.47	$ 20.10
Outstanding and exercisable at December 31, Weighted Avg. Exercise Price (in dollars per share)	$ 27.46	$ 23.34	$ 21.64
Shares exercised, Aggregate Intrinsic Value	$ 938	$ 1,496	$ 1,609