Allowance for Loan and Lease Loss and Credit Quality (Summary Of Reserve For Unfunded Commitments Activity) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Reserve for Unfunded Commitments [Roll Forward]
Balance, beginning of period	$ 4,130	$ 3,816	$ 3,963	$ 3,611
Net charge to other expense	164	116	331	321
Balance, end of period	4,294	3,932	4,294	3,932
Unfunded loan and lease commitments	$ 5,244,832	$ 4,839,882	$ 5,244,832	$ 4,839,882