Earnings Per Common Share (Summary Of Computation Of Basic And Diluted Earnings Per Common Share) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Earnings Per Share [Abstract]
Income available to common shareholders	$ 20,034	$ 16,938	$ 40,744	$ 46,936
Denominator for basic earnings per share (weighted average common shares outstanding)	15,411,981	15,405,902	15,411,986	15,405,906
Effect of dilutive options and warrants	0	0	0	3,784
Denominator for diluted earnings per share (weighted average common shares outstanding adjusted for the effect of dilutive options and warrants)	15,411,981	15,405,902	15,411,986	15,409,690
Basic earnings per common share	$ 1.30	$ 1.10	$ 2.64	$ 3.05
Diluted earnings per common share	$ 1.30	$ 1.10	$ 2.64	$ 3.05