Loans And Allowance For Loan Losses (Total Average Impaired Loans) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Loans And Allowance For Loan Losses [Line Items]
Non-accrual loans	$ 13,647	$ 21,429
Restructured loans (accruing)	66,609	49,353
Average impaired loans	80,256	70,782
Commercial Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Non-accrual loans	9,658	17,294
Restructured loans (accruing)	49,070	32,295
Average impaired loans	58,728	49,589
Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Non-accrual loans	3,989	4,135
Restructured loans (accruing)	17,539	17,058
Average impaired loans	$ 21,528	$ 21,193