Goodwill And Other Intangible Assets (Schedule Of Other Intangible Assets) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 178,005	$ 176,683
Accumulated amortization	(98,043)	(92,578)
Net carrying amount	79,962	84,105
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	100,138	100,146
Accumulated amortization	(43,825)	(40,661)
Net carrying amount	56,313	59,485
Purchased Software Costs [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	40,399	39,069
Accumulated amortization	(31,371)	(30,626)
Net carrying amount	9,028	8,443
Technology Licenses [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	28,800	28,800
Accumulated amortization	(22,550)	(21,006)
Net carrying amount	6,250	7,794
Trade Names and Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	7,800	7,800
Accumulated amortization	0	0
Net carrying amount	7,800	7,800
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	868	868
Accumulated amortization	(297)	(285)
Net carrying amount	$ 571	$ 583