CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 26, 2014	Sep. 27, 2013	Sep. 26, 2014	Sep. 27, 2013
Income Statement [Abstract]
Product revenue	$ 84,583	$ 98,713	$ 259,371	$ 277,965
Service revenue	23,478	24,205	66,311	63,753
Net revenue	108,061	122,918	325,682	341,718
Product cost of revenue	41,802	52,747	134,336	146,916
Service cost of revenue	12,831	13,379	35,789	33,953
Total cost of revenue	54,633	66,126	170,125	180,869
Gross profit	53,428	56,792	155,557	160,849
Operating expenses:
Research and development	22,803	24,560	70,176	75,631
Selling, general and administrative	32,114	32,527	98,640	100,220
Amortization of intangibles	1,661	2,001	5,329	6,099
Restructuring and related charges	388	259	821	925
Total operating expenses	56,966	59,347	174,966	182,875
Loss from operations	(3,538)	(2,555)	(19,409)	(22,026)
Interest income, net	47	47	191	141
Other income (expense), net	(261)	230	(376)	(70)
Loss from continuing operations before income taxes	(3,752)	(2,278)	(19,594)	(21,955)
Provision for (benefit from) income taxes	(4,830)	(38,953)	21,800	(45,723)
Income (loss) from continuing operations	1,078	36,675	(41,394)	23,768
Income from discontinued operations, net of taxes (including gain on disposal of $14,813, net of taxes, for the nine months ended September 27, 2013)	0	91	0	15,619
Net income (loss)	$ 1,078	$ 36,766	$ (41,394)	$ 39,387
Basic net income (loss) per share from:
Continuing operations	$ 0.01	$ 0.36	$ (0.44)	$ 0.22
Discontinued operations	$ 0.00	$ 0.00	$ 0.00	$ 0.14
Net income (loss)	$ 0.01	$ 0.36	$ (0.44)	$ 0.36
Diluted net income (loss) per share from:
Continuing operations	$ 0.01	$ 0.36	$ (0.44)	$ 0.22
Discontinued operations	$ 0.00	$ 0.00	$ 0.00	$ 0.14
Net income (loss)	$ 0.01	$ 0.36	$ (0.44)	$ 0.36
Shares used in per share calculation:
Basic	90,618	101,144	94,113	108,695
Diluted	91,800	102,723	94,113	109,879