Intangible Assets Gross Carrying Amount and Accumulated Amortization (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
Intangible Assets [Line Items]
Gross Assets	$ 711,233	$ 748,148	$ 769,992	$ 804,281
Accumulated Amortization	(599,466)	(608,239)
Net	111,767	139,909
Core-developed technology [Member]
Intangible Assets [Line Items]
Gross Assets	392,667	405,434
Accumulated Amortization	(357,007)	(359,500)
Net	35,660	45,934
Customer contracts and relationships [Member]
Intangible Assets [Line Items]
Gross Assets	242,627	262,930
Accumulated Amortization	(168,552)	(172,755)
Net	74,075	90,175
Trademarks and trade names [Member]
Intangible Assets [Line Items]
Gross Assets	64,808	68,205
Accumulated Amortization	(62,884)	(64,905)
Net	1,924	3,300
Other [Member]
Intangible Assets [Line Items]
Gross Assets	11,131	11,579
Accumulated Amortization	(11,023)	(11,079)
Net	$ 108	$ 500