Annual report pursuant to Section 13 and 15(d)

Related-Party Transactions - Additional Information (Detail)

v3.19.3.a.u2
Related-Party Transactions - Additional Information (Detail) - USD ($)
12 Months Ended
May 22, 2018
Jul. 25, 2017
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Follow-on Public Offering [Member]          
Related Party Transaction [Line Items]          
Common stock, issued and sold 4,057,500        
Common stock issued price per share $ 15.00        
Cellectis [Member]          
Related Party Transaction [Line Items]          
Minimum net worth required     $ 300,000,000    
Common stock, issued and sold   2,500,000      
Cellectis [Member] | License and Royalty [Member]          
Related Party Transaction [Line Items]          
Related party transaction, expenses from transactions with related party     328,000    
Cellectis [Member] | Restricted Stock Units [Member]          
Related Party Transaction [Line Items]          
Common stock, issued and sold       63,175  
Common stock issued price per share       $ 19.49  
Cellectis [Member] | Follow-on Public Offering [Member]          
Related Party Transaction [Line Items]          
Common stock, issued and sold 550,000     550,000  
Common stock issued price per share       $ 15.00  
General and Administrative Expense [Member] | Cellectis [Member]          
Related Party Transaction [Line Items]          
Related party transaction, expenses from transactions with related party     $ 1,300,000 $ 2,300,000 $ 2,000,000