Derivative Financial Instruments (Summary Of Gain/Loss On Derivative Instruments) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Foreign currency transaction gain (loss)	$ 10,814	$ 3,980	$ (1,097)
Foreign currency loss on foreign currency forward contracts	(13,268)	(7,312)	(3,788)
Foreign currency loss, net	$ (2,454)	$ (3,332)	$ (4,885)