Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Additional Information (Details)

v3.20.2
Stock-Based Compensation - Additional Information (Details) - USD ($)
1 Months Ended 3 Months Ended 9 Months Ended
Sep. 05, 2019
Sep. 07, 2017
May 15, 2015
Sep. 24, 2018
Aug. 25, 2016
Oct. 22, 2013
Mar. 20, 2007
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Sep. 17, 2020
Dec. 31, 2019
Nov. 02, 2010
Share-based Compensation Arrangement by Share-based Payment Award                            
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures               0 0 0 0      
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options               $ 406,000   $ 406,000        
Temporary Equity, Par or Stated Value Per Share               $ 0.001   $ 0.001     $ 0.001  
Employees | General and Administrative Expense                            
Share-based Compensation Arrangement by Share-based Payment Award                            
Allocated Share-based Compensation Expense               $ 41,000 $ 59,000 $ 120,000 $ 165,000      
Employees | Research and Development Expense                            
Share-based Compensation Arrangement by Share-based Payment Award                            
Allocated Share-based Compensation Expense               14,000 22,000 45,000 52,000      
Consultants | General and Administrative Expense                            
Share-based Compensation Arrangement by Share-based Payment Award                            
Allocated Share-based Compensation Expense               26,000 9,000 79,000 28,000      
Consultants | Research and Development Expense                            
Share-based Compensation Arrangement by Share-based Payment Award                            
Allocated Share-based Compensation Expense               $ 1,000 $ 1,000 $ 7,000 $ 1,000      
2007 Stock Plan [Member]                            
Share-based Compensation Arrangement by Share-based Payment Award                            
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number             71,429 7,052   7,052        
2007 Stock Plan [Member] | Maximum [Member]                            
Share-based Compensation Arrangement by Share-based Payment Award                            
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross             7,143              
2010 Stock Plan [Member]                            
Share-based Compensation Arrangement by Share-based Payment Award                            
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number               2,453,273   2,453,273       85,714
2010 Stock Plan [Member] | Maximum [Member]                            
Share-based Compensation Arrangement by Share-based Payment Award                            
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross 4,000,000 500,000 228,572 1,000,000 400,000 171,429                
2010 Stock Plan [Member] | Minimum [Member]                            
Share-based Compensation Arrangement by Share-based Payment Award                            
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross 1,000,000 400,000 171,429 500,000 228,572 85,714                
2020 Stock Plan [Member]                            
Share-based Compensation Arrangement by Share-based Payment Award                            
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number               0   0   4,000,000