Goodwill And Other Intangible Assets (Schedule Of Other Intangible Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 178,812	$ 176,683
Accumulated amortization	(100,635)	(92,578)
Net carrying amount	78,177	84,105
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	100,094	100,146
Accumulated amortization	(45,366)	(40,661)
Net carrying amount	54,728	59,485
Purchased Software Costs [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	41,250	39,069
Accumulated amortization	(31,641)	(30,626)
Net carrying amount	9,609	8,443
Technology Licenses [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	28,800	28,800
Accumulated amortization	(23,325)	(21,006)
Net carrying amount	5,475	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	(303)	(285)
Net carrying amount	$ 565	$ 583