Annual report pursuant to Section 13 and 15(d)

Commitments - Additional Information (Detail)

v3.20.1
Commitments - Additional Information (Detail) - USD ($)
1 Months Ended 12 Months Ended
May 31, 2015
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Jul. 31, 2010
Operating Leased Assets [Line Items]          
Incremental borrowing rate   12.00%      
ROU asset, impairment loss   $ 50,000 $ 0 $ 0  
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      
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        
ROU asset, impairment loss   $ 50,000