Goodwill And Other Intangible Assets (Schedule Of Intangible Assets With Estimable Useful Lives) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 45,253	$ 44,212
Accumulated Amortization	(35,920)	(34,351)
Valuation Allowance	(2,150)	(327)
Net Amount	7,183	9,534
Core Deposit Premium [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	31,270	31,270
Accumulated Amortization	(29,818)	(29,485)
Valuation Allowance	0	0
Net Amount	1,452	1,785
Mortgage Servicing Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	13,983	12,942
Accumulated Amortization	(6,102)	(4,866)
Valuation Allowance	(2,150)	(327)
Net Amount	$ 5,731	$ 7,749