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, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Earnings Per Share [Abstract]
Income available to common shareholders	$ 11,982	$ 18,917	$ 58,918	$ 67,138
Denominator for basic earnings per share (weighted average common shares outstanding)	15,405,894	15,398,909	15,405,902	15,398,919
Effect of dilutive options and warrants	0	0	3,284	1,722
Denominator for diluted earnings per share (weighted average common shares outstanding adjusted for the effect of dilutive options and warrants)	15,405,894	15,398,909	15,409,186	15,400,641
Basic earnings per common share	$ 0.78	$ 1.23	$ 3.82	$ 4.36
Diluted earnings per common share	$ 0.78	$ 1.23	$ 3.82	$ 4.36