Leases (Components Of Lease Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Leases [Abstract]
Amortization of right-of-use assets	$ 12	$ 24	$ 25	$ 64
Interest on lease liabilities	1	2	3	5
Operating lease cost	8,516	8,079	16,780	16,099
Variable lease cost	(1,593)	(833)	(2,744)	(652)
Total lease cost	$ 6,937	$ 7,272	$ 14,064	$ 15,516