Derivative Financial Instruments (Schedule Of Effect Of Derivative Instruments On Financial Performance) (Details) - Cash flow hedging - Foreign currency - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Derivatives Designated as Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss) Gain Recognized in Other Comprehensive (Loss) Income (Effective Portion)	$ (875)	$ 6,090
Derivatives Designated as Hedging Instruments | Operating expenses
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Loss Reclassified from Accumulated Other Comprehensive Loss (Effective Portion)	(1,763)	(13,027)
Derivatives Not Designated as Hedging Instruments | Other expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss) Gain Recognized in Income on Derivative	$ (1,030)	$ 1,669