Consolidated Statements of Operations (unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2016	Oct. 03, 2015	Oct. 01, 2016	Oct. 03, 2015
Income Statement [Abstract]
Product	$ 102,816	$ 98,572	$ 280,374	$ 280,587
Licensing and services	10,409	11,143	28,572	24,185
Total revenue	113,225	109,715	308,946	304,772
Costs and expenses:
Cost of product revenue	45,695	49,415	125,412	138,250
Cost of licensing and services revenue	106	451	580	715
Research and development	27,747	37,619	91,270	104,813
Selling, general, and administrative	29,244	23,819	75,857	73,096
Amortization of acquired intangible assets	8,260	8,941	25,292	20,824
Restructuring charges	317	6,818	8,316	15,780
Acquisition related charges	0	610	94	22,078
Impairment of intangible assets	7,866	0	7,866	0
Costs and Expenses	119,235	127,673	334,687	375,556
Loss from operations	(6,010)	(17,958)	(25,741)	(70,784)
Interest expense	(5,235)	(5,754)	(15,257)	(12,870)
Other income (expense), net	209	(841)	3,558	(1,095)
Loss before income taxes and equity in net loss of an unconsolidated affiliate	(11,036)	(24,553)	(37,440)	(84,749)
Income tax expense	971	309	7,410	29,030
Equity in net loss of an unconsolidated affiliate, net of tax	(407)	0	(1,085)	0
Net loss	$ (12,414)	$ (24,862)	$ (45,935)	$ (113,779)
Net loss per share, basic and diluted (in usd per shares)	$ (0.10)	$ (0.21)	$ (0.38)	$ (0.97)
Shares used in per share calculations, basic and diluted (in shares)	120,584	117,669	119,596	117,151