Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Additional Information (Detail)

v3.20.2
Summary of Significant Accounting Policies - Additional Information (Detail)
 3 Months Ended 6 Months Ended
Jun. 30, 2020
USD ($)
Jun. 30, 2019
USD ($)
Jun. 30, 2020
USD ($)
Jun. 30, 2019
USD ($)
Dec. 31, 2019
USD ($)
Jan. 01, 2019
USD ($)
Summary Of Significant Accounting Policies [Line Items]            
Maturity period of highly liquid investments     three months or less      
Realized gains or losses on marketable securities $ 0 $ 0 $ 0 $ 0    
Number of securities in unrealized loss position for more than 12 months 0   0   0  
Grants receivable recognized $ 1,000,000 $ 500,000 $ 2,400,000 $ 1,200,000    
Grants receivable 1,000,000   1,000,000   $ 1,100,000  
Grants remaining to be awarded 5,200,000   5,200,000      
Operating lease right-of use assets 2,930,022   2,930,022   3,043,826  
Operating lease liabilities 3,753,335   3,753,335      
Current portion of lease liabilities 638,051   638,051   631,889  
Long-term portion of lease liabilities $ 3,115,284   $ 3,115,284   $ 3,264,128  
Accounting Standards Update 2016-02 [Member]            
Summary Of Significant Accounting Policies [Line Items]            
Operating lease right-of use assets           $ 3,300,000
Operating lease liabilities           4,100,000
Current portion of lease liabilities           600,000
Long-term portion of lease liabilities           $ 3,500,000