CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 02, 2015	Sep. 26, 2014	Oct. 02, 2015	Sep. 26, 2014
Income Statement [Abstract]
Product	$ 57,245	$ 84,583	$ 215,165	$ 259,371
Services	26,060	23,478	75,259	66,311
Total net revenue	83,305	108,061	290,424	325,682
Product	23,584	41,802	95,021	134,336
Services	13,490	12,831	39,759	35,789
Total cost of revenue	37,074	54,633	134,780	170,125
Total gross profit	46,231	53,428	155,644	155,557
Operating expenses:
Research and development	21,679	22,803	65,824	70,176
Selling, general and administrative	28,966	32,114	91,443	98,640
Amortization of intangibles	1,446	1,661	4,338	5,329
Restructuring and related charges	397	388	626	821
Total operating expenses	52,488	56,966	162,231	174,966
Loss from operations	(6,257)	(3,538)	(6,587)	(19,409)
Interest income, net	30	47	102	191
Other income (expense), net	148	(261)	(299)	(376)
Loss on impairment of long-term investment			(2,505)	0
Loss before income taxes	(6,079)	(3,752)	(9,289)	(19,594)
(Benefit from) provision for income taxes	(1,268)	(4,830)	(827)	21,800
Net income (loss)	$ (4,811)	$ 1,078	$ (8,462)	$ (41,394)
Net income (loss) per share:
Basic	$ (0.05)	$ 0.01	$ (0.10)	$ (0.44)
Diluted	$ (0.05)	$ 0.01	$ (0.10)	$ (0.44)
Shares used in per share calculation:
Basic	87,991	90,618	88,359	94,113
Diluted	87,991	91,800	88,359	94,113