Commitments (Schedule Of Future Minimum Lease Payments Under Noncancelable Operating Leases And Future Minimum Capital Lease Payments) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Commitments [Abstract]
Capital Leases, 2019	$ 1,746
Capital Leases, 2020	1,781
Capital Leases, 2021	1,816
Capital Leases, 2022	1,853
Capital Leases, 2023	465
Capital Leases, thereafter	0
Capital Leases, total minimum lease payments	7,661
Less: amount representing interest	1,514
Present value of minimum lease payments	6,147
Less: current installments	1,168	$ 1,025
Capital lease obligations, less current installments	4,979	$ 6,147
Operating Leases, 2019	15,272
Operating Leases, 2020	14,518
Operating Leases, 2021	12,203
Operating Leases, 2022	10,466
Operating Leases, 2023	9,890
Operating Leases, thereafter	47,868
Operating Leases, total minimum lease payments	$ 110,217