Notes Payable - Schedule of Future Minimum Payments for Notes Payable (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Non-current portion of notes payable	$ 19,740	$ 19,511
First Term Loan [Member]
Debt Instrument [Line Items]
2016	2,338
2017	2,332
2018	2,332
2019	2,332
2020 and beyond	22,751
Total minimum payments	32,085
Less: Amount representing interest	(11,085)
Less: Amount representing closing and repayment fees	(1,000)
Present value of minimum payments	20,000
Total minimum payments	32,085
Present value of minimum payments	20,000
Less: Unamortized debt discount	(409)
Plus: Accretion of closing and repayment fees	149
Notes payable, net	19,740
Less: Notes payable, current portion	0
Non-current portion of notes payable	19,740
Notes payable, net	$ 19,740