Segment Information (Schedule Of Assets By Geographic Area) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Assets	$ 896,714	$ 893,275
Operating Segments [Member] | Americas [Member]
Segment Reporting Information [Line Items]
Assets	375,598	384,054
Operating Segments [Member] | Germany [Member]
Segment Reporting Information [Line Items]
Assets	31,942	36,782
Operating Segments [Member] | Other EMEA [Member]
Segment Reporting Information [Line Items]
Assets	384,679	369,302
Operating Segments [Member] | Asia Pacific [Member]
Segment Reporting Information [Line Items]
Assets	$ 104,495	$ 103,137