Loans And Allowance For Loan Losses (Outstanding Balance Of Loans Classified As Troubled Debt Restructurings) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Loans And Allowance For Loan Losses [Line Items]
Restructured loans	$ 110,608	$ 59,074
Balance 90 days past due at any time during previous 12 months	1,031
Commercial Portfolio Segment [Member] | Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Restructured loans	77,400
Balance 90 days past due at any time during previous 12 months	0
Commercial Portfolio Segment [Member] | Real Estate - Construction And Land [Member]
Loans And Allowance For Loan Losses [Line Items]
Restructured loans	776
Balance 90 days past due at any time during previous 12 months	0
Commercial Portfolio Segment [Member] | Real Estate - Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Restructured loans	12,394
Balance 90 days past due at any time during previous 12 months	0
Personal Banking Portfolio Segment [Member] | Real Estate - Personal [Member]
Loans And Allowance For Loan Losses [Line Items]
Restructured loans	7,760
Balance 90 days past due at any time during previous 12 months	278
Personal Banking Portfolio Segment [Member] | Consumer [Member]
Loans And Allowance For Loan Losses [Line Items]
Restructured loans	5,389
Balance 90 days past due at any time during previous 12 months	81
Personal Banking Portfolio Segment [Member] | Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Restructured loans	204
Balance 90 days past due at any time during previous 12 months	42
Personal Banking Portfolio Segment [Member] | Consumer Credit Card [Member]
Loans And Allowance For Loan Losses [Line Items]
Restructured loans	6,685
Balance 90 days past due at any time during previous 12 months	$ 630