Operating Segments and Geographic Information (Schedule Of Geographical Long-Lived Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Total long-lived assets	$ 44,090	$ 49,490
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total long-lived assets	29,420	32,954
International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total long-lived assets	$ 14,670	$ 16,536