Loans And Allowance For Loan Losses (Summary Classification Of Held To Maturity Loan Portfolio) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Loans And Allowance For Loan Losses [Line Items]
Total loans	$ 13,230,241	$ 12,436,692
Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	4,770,883	4,397,893
Real Estate - Construction And Land [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	800,545	624,070
Real Estate - Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	2,520,528	2,355,544
Real Estate - Personal [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	1,968,005	1,915,953
Consumer [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	1,972,969	1,924,365
Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	417,591	432,981
Consumer Credit Card [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	760,022	779,744
Overdrafts [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	$ 19,698	$ 6,142