Earnings Per Common Share (Summary Of Computation Of Basic And Diluted Earnings Per Common Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Earnings Per Share [Abstract]
Income available to common shareholders	$ 22,163	$ 28,241	$ 47,618	$ 59,364
Denominator for basic earnings per share (weighted average common shares outstanding)	16,560,545	15,285,532	16,106,043	15,286,932
Effect of dilutive options and warrants	82,026	132,075	87,600	137,653
Denominator for diluted earnings per share (weighted average common shares outstanding adjusted for the effect of dilutive options and warrants)	16,642,571	15,417,607	16,193,643	15,424,585
Basic earnings per common share	$ 1.34	$ 1.85	$ 2.96	$ 3.88
Diluted earnings per common share	$ 1.33	$ 1.83	$ 2.94	$ 3.85