Leases (Summary Of Lease Costs By Type) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Leases [Abstract]
Amortization of right-of-use assets	$ 21	$ 27	$ 73	$ 76
Interest on lease liabilities		3	3	8
Operating lease cost	494	462	1,368	1,379
Variable lease cost	147	138	446	417
Total lease cost	$ 662	$ 630	$ 1,890	$ 1,880