Segment Reporting - Schedule of Revenue by Geographic Segments (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]
Total	$ 41,085	$ 38,496	$ 83,124	$ 72,845
% of Total	100.00%	100.00%	100.00%	100.00%
United States [Member]
Segment Reporting Information [Line Items]
Total	23,359	21,251	47,506	37,918
% of Total	56.80%	55.20%	57.20%	52.10%
Asia [Member]
Segment Reporting Information [Line Items]
Total	11,664	11,755	24,553	22,471
% of Total	28.40%	30.50%	29.50%	30.80%
United Kingdom [Member]
Segment Reporting Information [Line Items]
Total	1,562	1,196	2,945	2,674
% of Total	3.80%	3.10%	3.50%	3.70%
Germany [Member]
Segment Reporting Information [Line Items]
Total	$ 4,500	$ 4,294	$ 8,120	$ 9,782
% of Total	11.00%	11.20%	9.80%	13.40%