Segment And Geographic Information (Schedule Of Geographic Allocation Of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 107,570	$ 106,693	$ 316,373	$ 289,549
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	31,887	33,162	92,840	86,706
Switzerland [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	13,837	13,929	41,712	36,246
France [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	8,768	9,295	26,582	27,435
Korea [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	10,807	8,707	31,361	21,927
Singapore [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	10,655	5,987	31,005	16,725
Other Asia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	14,638	18,828	44,613	52,608
Other Europe [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	16,529	14,636	47,052	40,794
Other International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 449	$ 2,149	$ 1,208	$ 7,108