Derivative Financial Instruments (Schedule Of Derivative Instruments Fair Value And Balance Sheet Classification) (Details) - Forward exchange contracts [Member] - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Prepaid And Other Current Assets [Member]
Derivative instruments in asset positions, Forward exchange contracts	$ 634	$ 40
Other Long-Term Assets [Member]
Derivative instruments in asset positions, Forward exchange contracts	56	6
Accounts Payable And Accrued Liabilities [Member]
Derivative instruments in liability positions, Forward exchange contracts	$ 10	919
Other Long-Term Liabilities [Member]
Derivative instruments in liability positions, Forward exchange contracts		$ 74