Commitments (Schedule Of Future Minimum Lease Payments Under Noncancelable Operating Leases And Future Minimum Capital Lease Payments) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Commitments [Abstract]
Capital Leases, 2017	$ 2,633
Capital Leases, 2018	2,793
Capital Leases, 2019	2,972
Capital Leases, 2020	3,167
Capital Leases, 2021	3,382
Capital Leases, thereafter	4,513
Capital Leases, total minimum lease payments	19,460
Less: amount representing interest	11,392
Present value of minimum lease payments	8,068
Less: current installments	896	$ 778
Capital lease obligations, less current installments	7,172	$ 8,067
Operating Leases, 2017	12,013
Operating Leases, 2018	10,614
Operating Leases, 2019	9,497
Operating Leases, 2020	6,967
Operating Leases, 2021	4,736
Operating Leases, thereafter	17,096
Operating Leases, total minimum lease payments	$ 60,923