Goodwill And Other Intangible Assets (Schedule Of Other Intangible Assets) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 167,679	$ 167,103
Accumulated amortization	(73,584)	(70,817)
Net carrying amount	94,095	96,286
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	100,070	100,053
Accumulated amortization	(29,485)	(27,883)
Net carrying amount	70,585	72,170
Purchased Software Costs [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	32,141	31,582
Accumulated amortization	(28,777)	(28,508)
Net carrying amount	3,364	3,074
Technology Licenses [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	26,800	26,800
Accumulated amortization	(15,079)	(14,189)
Net carrying amount	11,721	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	(243)	(237)
Net carrying amount	$ 625	$ 631