Consolidated Statements of Operations (unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 02, 2016	Jul. 04, 2015	Jul. 02, 2016	Jul. 04, 2015
Income Statement [Abstract]
Product	$ 89,335	$ 96,300	$ 177,558	$ 182,015
Licensing and services	9,874	10,160	18,163	13,042
Total revenue	99,209	106,460	195,721	195,057
Costs and expenses:
Cost of product revenue	40,710	48,163	79,717	88,835
Cost of licensing and services revenue	73	171	474	264
Research and development	30,915	39,552	63,523	67,194
Selling, general, and administrative	23,005	28,189	46,613	49,277
Amortization of acquired intangible assets	8,311	8,941	17,032	11,883
Restructuring charges	2,568	4,068	7,999	8,962
Acquisition related charges	0	3,270	94	21,468
Costs and Expenses	105,582	132,354	215,452	247,883
Loss from operations	(6,373)	(25,894)	(19,731)	(52,826)
Interest expense	(5,062)	(5,505)	(10,022)	(7,116)
Other income (expense), net	2,532	(115)	3,349	(254)
Loss before income taxes and equity in net loss of an unconsolidated affiliate	(8,903)	(31,514)	(26,404)	(60,196)
Income tax expense	4,539	4,056	6,439	28,721
Equity in net loss of an unconsolidated affiliate, net of tax	(368)	0	(678)	0
Net loss	$ (13,810)	$ (35,570)	$ (33,521)	$ (88,917)
Net loss per share, basic and diluted (in usd per shares)	$ (0.12)	$ (0.30)	$ (0.28)	$ (0.76)
Shares used in per share calculations, basic and diluted (in shares)	119,445	116,903	119,125	116,883