Segment Reporting - Revenues by Geographic Area, Based on Billing Location of Customer (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	Dec. 31, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues, net	$ 18,218	$ 14,032	$ 35,373	$ 27,006
Total long-lived assets, net	13,426		13,426		9,224
Reportable Geographical Components [Member] | United States of America [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues, net	12,645	10,321	24,623	19,912
Total long-lived assets, net	13,054		13,054		8,839
Reportable Geographical Components [Member] | International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues, net	5,573	3,711	10,750	7,094
Total long-lived assets, net	$ 372		$ 372		$ 385