Segment And Geographic Information (Schedule Of Geographic Allocation Of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 66,117	$ 59,203	$ 183,975	$ 168,779
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	15,726	6,132	27,184	17,643
France [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	6,436	6,636	19,430	18,450
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	6,119	6,704	19,079	18,706
Korea [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	4,449	5,329	13,886	15,771
Switzerland [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	4,887	5,332	14,100	15,364
Other Asia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	15,665	16,489	51,714	46,018
Other Europe [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	9,447	8,568	27,527	24,138
Other International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 3,388	$ 4,013	$ 11,055	$ 12,689