Restatement and Revisions on the Condensed Consolidated Statements of Operations (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Revenue	$ 56,063	[1]	$ 54,223
Cost of goods sold	44,306	[1]	42,817
Gross profit	11,757	[1]	11,406
Operating expenses:
Research and development	9,707	[1]	10,538
Sales and marketing	3,586	[1]	3,023
General and administrative	5,059	[1]	6,601
Amortization of purchased intangible assets	321	[1]	354
Restructuring charges	325	[1]	130
Total operating expenses	23,508	[1]	22,947
Loss from operations	(11,751)	[1]	(11,541)
Interest income	131	[1]	132
Interest expense	(163)	[1]	(154)
Other expense, net	(274)	[1]	(275)
Total interest and other expense, net	(306)	[1]	(297)
Loss before income taxes	(12,057)	[1]	(11,838)
Income tax (expense) benefit	(183)	[1]	60
Net loss	(12,240)	[1],[2],[3]	(11,608)
Basic and diluted net income (loss) per share:
Net loss	$ (0.40)	[1]	$ (0.46)
Weighted average shares used to compute basic and diluted net loss per share	30,574,032	[1]	24,870,684
Previously Reported
Revenue	56,063
Cost of goods sold	44,333
Gross profit	11,730
Operating expenses:
Research and development	9,707
Sales and marketing	3,586
General and administrative	8,545
Amortization of purchased intangible assets	321
Restructuring charges	325
Total operating expenses	22,484
Loss from operations	(10,754)
Interest income	131
Interest expense	(163)
Other expense, net	(274)
Total interest and other expense, net	(306)
Loss before income taxes	(11,060)
Income tax (expense) benefit	596
Net loss	(10,464)	[4]
Basic and diluted net income (loss) per share:
Net loss	$ (0.34)
Weighted average shares used to compute basic and diluted net loss per share	30,574,032
Corrections
Cost of goods sold	(27)
Gross profit	27
Operating expenses:
General and administrative	1,024
Total operating expenses	1,024
Loss from operations	(997)
Loss before income taxes	(997)
Net loss	(997)
Revision for Measurement Period Adjustments
Operating expenses:
Income tax (expense) benefit	(779)
Net loss	(779)
Restated and Revised
Revenue	56,063
Cost of goods sold	44,306
Gross profit	11,757
Operating expenses:
Research and development	9,707
Sales and marketing	3,586
General and administrative	9,569
Amortization of purchased intangible assets	321
Restructuring charges	325
Total operating expenses	23,508
Loss from operations	(11,751)
Interest income	131
Interest expense	(163)
Other expense, net	(274)
Total interest and other expense, net	(306)
Loss before income taxes	(12,057)
Income tax (expense) benefit	(183)
Net loss	$ (12,240)
Basic and diluted net income (loss) per share:
Net loss	$ (0.40)
Weighted average shares used to compute basic and diluted net loss per share	30,574,032

[1] Restated and Revised, see Note 2

[2] Restated and Revised, see Note 2

[3] Restated and Revised, see Note 2

[4] The Company’s condensed consolidated statement of cash flows for the three months ended March 31, 2013 was previously restated for amounts related to purchases of property and equipment that were inadvertently overstated resulting in the overstatement of cash used in investing activities by $1.1 million and the overstatement of net cash provided by operating activities by the same amount.