Segment Reporting - Classification of Revenue by Geography (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Segment Reporting Information [Line Items]
Total revenue	$ 8,389	$ 6,035	$ 21,283	$ 16,480
North America [Member] | Reportable Geographical Components [Member]
Segment Reporting Information [Line Items]
Total revenue	5,333	4,749	15,028	11,809
Europe & Middle East [Member] | Reportable Geographical Components [Member]
Segment Reporting Information [Line Items]
Total revenue	1,592	865	3,702	2,863
Asia Pacific [Member] | Reportable Geographical Components [Member]
Segment Reporting Information [Line Items]
Total revenue	$ 1,464	$ 421	$ 2,553	$ 1,808