Loans And Allowance For Loan Losses (Summary Classification Of Held To Maturity Loan Portfolio) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Loans And Allowance For Loan Losses [Line Items]
Total loans	$ 9,982,686	$ 9,831,384
Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	3,206,594	3,134,801
Real Estate - Construction And Land [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	353,659	355,996
Real Estate - Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	2,213,353	2,214,975
Real Estate - Personal [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	1,626,106	1,584,859
Consumer [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	1,408,246	1,289,650
Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	420,219	437,567
Consumer Credit Card [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	750,671	804,245
Overdrafts [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	3,838	9,291
Commercial Portfolio Segment [Member] | Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	3,206,594	3,134,801
Commercial Portfolio Segment [Member] | Real Estate - Construction And Land [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	353,659	355,996
Commercial Portfolio Segment [Member] | Real Estate - Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	2,213,353	2,214,975
Personal Banking Portfolio Segment [Member] | Real Estate - Personal [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	1,626,106	1,584,859
Personal Banking Portfolio Segment [Member] | Consumer [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	1,408,246	1,289,650
Personal Banking Portfolio Segment [Member] | Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	420,219	437,567
Personal Banking Portfolio Segment [Member] | Consumer Credit Card [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	750,671	804,245
Personal Banking Portfolio Segment [Member] | Overdrafts [Member]
Loans And Allowance For Loan Losses [Line Items]
Total loans	$ 3,838	$ 9,291