Intangible Assets (Schedule Of Finite-Lived Intangible Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 272,372	$ 248,080
Accumulated Amortization	(163,709)	(139,884)
Net Carrying Amount	108,663	108,196
Capitalized Software Development Costs [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	103,887	80,682
Accumulated Amortization	(39,180)	(30,434)
Net Carrying Amount	64,707	50,248
Acquired Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	94,124	93,976
Accumulated Amortization	(79,485)	(69,908)
Net Carrying Amount	14,639	24,068
Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	31,513	30,221
Accumulated Amortization	(17,573)	(14,941)
Net Carrying Amount	13,940	15,280
Other [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	42,848	43,201
Accumulated Amortization	(27,471)	(24,601)
Net Carrying Amount	$ 15,377	$ 18,600