Accounts Payable and Accrued Liabilities - Summary of Accounts Payable and Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Payables And Accruals [Abstract]
Accounts payable	$ 3,905	$ 5,525
Accrued research and development expenses	3,624	2,435
Accrued professional fees	356	531
Deferred rent	196	129
Other	148	84
Total accounts payable and accrued liabilities	$ 8,229	$ 8,704