Restructuring Charges (Schedule Of Restructuring And Related Costs) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Restructuring Charges [Abstract]
Severance charges	$ 0	$ 0	$ 0	$ 6,453
Other charges, net	103	13	(212)	71
Total restructuring charges, net	$ 103	$ 13	$ (212)	$ 6,524

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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