Goodwill And Other Intangible Assets (Schedule Of Other Intangible Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 172,996	$ 167,103
Accumulated amortization	(82,132)	(70,817)
Net carrying amount	90,864	96,286
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	100,200	100,053
Accumulated amortization	(34,372)	(27,883)
Net carrying amount	65,828	72,170
Purchased Software Costs [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	35,328	31,582
Accumulated amortization	(29,612)	(28,508)
Net carrying amount	5,716	3,074
Technology Licenses [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	28,800	26,800
Accumulated amortization	(17,887)	(14,189)
Net carrying amount	10,913	12,611
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	(261)	(237)
Net carrying amount	$ 607	$ 631