Other Comprehensive Income (Loss) (Schedule Of Tax Effects Of The Components Of Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Other Comprehensive Income (Loss) [Abstract]
Defined benefit pension plan adjustments, Before-Tax Amount	$ 427		$ 1,280
Defined benefit pension plan adjustments, Tax (Expense) Benefit	(179)		(461)
Defined benefit pension plan adjustments, Net-of-Tax Amount	248		819
Foreign currency translation adjustment, Before-Tax Amount	(708)	$ (1,792)	500	$ (4,633)
Foreign currency translation adjustment, Tax (Expense) Benefit	297	417	(239)	1,524
Foreign currency translation adjustment, Net-of-Tax Amount	(411)	(1,375)	261	(3,109)
Unrealized gain (loss) in fair value of investments, Before-Tax Amount	(145)	(2)	(403)	(140)
Unrealized gain (loss) in fair value of investments, Tax (Expense) Benefit	66		179	54
Unrealized gain (loss) in fair value of investments, Net-of-Tax Amount	(79)	(2)	(224)	(86)
Unrealized gain (loss) in fair value of interest rate swap, Before-Tax Amount		77	(45)	250
Unrealized gain (loss) in fair value of interest rate swap, Tax (Expense) Benefit		(30)	21	(98)
Unrealized gain (loss) in fair value of interest rate swap, Net-of-Tax Amount		47	(24)	152
Total other comprehensive income (loss), Before-Tax Amount	(426)	(1,717)	1,332	(4,523)
Total other comprehensive income (loss), Tax (Expense) Benefit	184	387	(500)	1,480
Total other comprehensive (loss) income, net of tax	$ (242)	$ (1,330)	$ 832	$ (3,043)