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		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share [Abstract]
Income available to common shareholders	$ 18,303	$ 19,029	$ 59,749	$ 59,773
Denominator for basic earnings per share (weighted average common shares outstanding)	15,392,421	15,411,972	15,395,320	15,411,981
Effect of dilutive options and warrants	21,243	0	18,305	0
Denominator for diluted earnings per share (weighted average common shares outstanding adjusted for the effect of dilutive options and warrants)	15,413,664	15,411,972	15,413,625	15,411,981
Basic earnings per common share	$ 1.19	$ 1.23	$ 3.88	$ 3.88
Diluted earnings per common share	$ 1.19	$ 1.23	$ 3.88	$ 3.88