Comprehensive Income (Schedule Of Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			$ (34,621)	$ (38,090)
Current-period other comprehensive (loss) income			10,148	9,297
Reclassified from accumulated OCI into income			(792)	2,983
Income tax (benefit) expense	$ (1,186)	$ (1,436)	(2,146)	3,275
Ending Balance	(23,119)	(29,085)	(23,119)	(29,085)
Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			(37,174)	(31,871)
Current-period other comprehensive (loss) income			15,664	8,166
Income tax (benefit) expense			120	1,944
Ending Balance	(21,630)	(25,649)	(21,630)	(25,649)
Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			(669)	(857)
Current-period other comprehensive (loss) income			26	549
Income tax (benefit) expense			(17)	134
Ending Balance	(626)	(442)	(626)	(442)
Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			3,222	(5,362)
Current-period other comprehensive (loss) income			(5,542)	582
Reclassified from accumulated OCI into income			(792)	2,983
Income tax (benefit) expense			(2,249)	1,197
Ending Balance	$ (863)	$ (2,994)	$ (863)	$ (2,994)