Quarterly report pursuant to Section 13 or 15(d)

Commitments - Additional Information (Detail)

v3.10.0.1
Commitments - Additional Information (Detail) - USD ($)
1 Months Ended 3 Months Ended 6 Months Ended
May 31, 2015
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Jul. 31, 2010
Operating Leased Assets [Line Items]            
Rent expense   $ 100,000 $ 100,000 $ 200,000 $ 200,000  
Amount payable upon the achievement of specified regulatory milestone           $ 18,000,000
Operating lease term July 2014 through December 2019 [Member]            
Operating Leased Assets [Line Items]            
Lease renewal term       5 years    
Future minimum payments for noncancelable operating lease   $ 1,000,000   $ 1,000,000    
Operating lease term September 2015 through September 2020 [Member]            
Operating Leased Assets [Line Items]            
Percentage of base rent escalator 3.00%          
Rent expense $ 33,000          
Lease agreement rent expense for future period $ 39,000