Information Regarding Net Revenue by Geographic Region (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012		Jun. 30, 2013	Jun. 30, 2012
Segment Reporting Information [Line Items]
Net revenue	$ 23,595	$ 23,856	[1]	$ 44,659	$ 45,062	[1]
Percentage of net revenue	100.00%	100.00%		100.00%	100.00%
Americas
Segment Reporting Information [Line Items]
Net revenue	12,063	12,619		22,324	22,825
Percentage of net revenue	51.00%	53.00%		50.00%	51.00%
Americas | United States
Segment Reporting Information [Line Items]
Net revenue	11,908	12,348		21,943	22,495
Americas | Other
Segment Reporting Information [Line Items]
Net revenue	155	271		381	330
Europe
Segment Reporting Information [Line Items]
Net revenue	8,846	7,842		16,745	15,374
Percentage of net revenue	38.00%	33.00%		37.00%	34.00%
Europe | Other
Segment Reporting Information [Line Items]
Net revenue	2,163	2,366		4,523	5,085
Europe | Germany
Segment Reporting Information [Line Items]
Net revenue	6,683	5,476		12,222	10,289
Asia-Pacific
Segment Reporting Information [Line Items]
Net revenue	2,686	3,395		5,590	6,863
Percentage of net revenue	11.00%	14.00%		13.00%	15.00%
Asia-Pacific | Other
Segment Reporting Information [Line Items]
Net revenue	947	1,175		2,377	2,270
Asia-Pacific | Singapore
Segment Reporting Information [Line Items]
Net revenue	$ 1,739	$ 2,220		$ 3,213	$ 4,593

[1] Certain amounts shown in the table above have changed as compared to amounts reported in prior periods as noted in Item 1, Financial Statements, Note 1 of Notes to Condensed Consolidated Financial Statements, Reclassifications and Restatements, for more details.