Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Additional Information (Detail)

v3.20.1
Summary of Significant Accounting Policies - Additional Information (Detail)
12 Months Ended
Dec. 31, 2019
USD ($)
Segment
GeographicalAreas
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Jan. 01, 2019
USD ($)
Summary Of Significant Accounting Policies [Line Items]        
Number of operating segment | Segment 1      
Number of geographic segment | GeographicalAreas 1      
Maturity period of highly liquid investments three months or less      
Realized gains or losses on marketable securities $ 0 $ 0 $ 0  
Number of securities in unrealized loss position for more than 12 months 0 0    
Impairment of long-lived assets $ 0 $ 0    
Provision for unrecognized tax benefits or expense 0 0    
Grants receivable recognized 3,600,000 1,200,000    
Grants receivable 1,100,000 $ 500,000    
Grants remaining to be awarded 8,300,000      
Operating lease right-of use assets 3,043,826      
Operating lease liabilities 3,896,017      
Current portion of lease liabilities 631,889      
Long-term portion of lease liabilities $ 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
Earliest Tax Year [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Tax position for all open tax years 2008      
Latest Tax Year [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Tax position for all open tax years 2019      
Minimum [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Property and equipment, estimated useful lives 3 years      
Maximum [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Property and equipment, estimated useful lives 5 years      
Level 1 [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Liabilities $ 0      
Level 2 [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Liabilities $ 0