Accumulated Other Comprehensive Income (Summary Of Accumulated Other Comprehensive Income) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 12,075	[1]
Net current-period other comprehensive income	8,489
Balance	20,564
Foreign Currency Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	14,784
Net current-period other comprehensive income	8,389
Balance	23,173
Unrealized Gain (Losses) On Available-For-Sale Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	10
Net current-period other comprehensive income	(3)
Balance	7
Accrued Pension Service Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(2,719)
Net current-period other comprehensive income	103
Balance	$ (2,616)

[1] Certain 2016 balances have been reclassified to conform to the 2017 presentation (see Note 2 - Summary of Significant Accounting Policies - Reclassifications).