Intangible Assets Gross Carrying Amount and Accumulated Amortization (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
Intangible Assets [Line Items]
Gross Assets	$ 704,816	$ 702,507	$ 711,233	$ 748,148
Accumulated Amortization	(622,083)	(600,575)
Net	82,733	101,932
Core-developed technology [Member]
Intangible Assets [Line Items]
Gross Assets	392,752	388,981
Accumulated Amortization	(370,894)	(358,092)
Net	21,858	30,889
Customer contracts and relationships [Member]
Intangible Assets [Line Items]
Gross Assets	236,974	238,379
Accumulated Amortization	(176,528)	(168,885)
Net	60,446	69,494
Trademarks and trade names [Member]
Intangible Assets [Line Items]
Gross Assets	64,010	64,069
Accumulated Amortization	(63,619)	(62,571)
Net	391	1,498
Other [Member]
Intangible Assets [Line Items]
Gross Assets	11,080	11,078
Accumulated Amortization	(11,042)	(11,027)
Net	$ 38	$ 51