Intangible Assets Gross Carrying Amount and Accumulated Amortization (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Intangible Assets [Line Items]
Gross Assets	$ 718,404	$ 748,148	$ 800,703	$ 804,281
Accumulated Amortization	(601,268)	(608,239)
Net	117,136	139,909
Core-developed technology [Member]
Intangible Assets [Line Items]
Gross Assets	392,427	405,434
Accumulated Amortization	(356,567)	(359,500)
Net	35,860	45,934
Customer contracts and relationships [Member]
Intangible Assets [Line Items]
Gross Assets	249,188	262,930
Accumulated Amortization	(170,270)	(172,755)
Net	78,918	90,175
Trademarks and trade names [Member]
Intangible Assets [Line Items]
Gross Assets	65,709	68,205
Accumulated Amortization	(63,406)	(64,905)
Net	2,303	3,300
Other [Member]
Intangible Assets [Line Items]
Gross Assets	11,080	11,579
Accumulated Amortization	(11,025)	(11,079)
Net	$ 55	$ 500