Leases (Components Of Lease Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Leases [Abstract]
Operating lease expense	$ 1,260	$ 1,537	$ 2,651	$ 3,015
Finance lease expense:
Amortization of right-of-use assets	38	29	79	61
Interest on lease liabilities	4	8	8	11
Total finance lease expense	42	37	87	72
Short-term lease expense	68	401	147	539
Variable lease expense	$ (151)	$ 1,085	$ 568	$ 1,766