Income Taxes (Schedule Of Effective Income Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Abstract]
Computed expected tax expense	$ 17,112	$ 20,020	$ 3,458
Foreign tax differential	(16,384)	(19,032)	(88)
State income tax expense, net of federal income tax benefit	25	191	310
Subpart F income	2,202	683	711
IRC Section 162(m) excess officer's compensatio	172
Non-deductible stock-based compensation	133	218	155
Excess tax benefit related to stock-based compensation	(34)	(1,858)
Increase in uncertain tax positions	25	61	36
Adjustment for prior years	(431)	1,894
Change in Federal tax rate		(16,945)
Adjustment to contingent consideration		(429)	(634)
Change in valuation allowance			(15)
Other	67	336	(89)
Total income tax expense (benefit)	$ 2,887	$ (14,861)	$ 3,844