Quarterly report pursuant to Section 13 or 15(d)

Common Stock - Stock Options - Additional Information (Detail)

v3.20.2
Common Stock - Stock Options - Additional Information (Detail) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Common shares reserved for options currently outstanding 129,470   129,470   50,498
Unrecognized compensation expense related to stock options granted $ 1.6   $ 1.6    
Anti-dilutive securities excluded from earning per share computation 1,397,119 256,882 1,397,119 256,882  
Warrant [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Anti-dilutive securities excluded from earning per share computation 1,267,418   1,267,418    
Stock Options [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Anti-dilutive securities excluded from earning per share computation 129,470   129,470    
Restricted Stock Unit [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Anti-dilutive securities excluded from earning per share computation 231   231    
Stock Options [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Weighted-average period, restricted stock awards     2 years 1 month 6 days    
Stock Options [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     4 years    
Stock Options [Member] | Minimum [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award expiration period     7 years    
Stock Options [Member] | Minimum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     1 year    
Stock Options [Member] | Maximum [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award expiration period     10 years    
Stock Options [Member] | Maximum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
Restricted Stock Unit [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     4 years    
Common shares reserved for awards currently outstanding 231   231   500
Weighted-average period, restricted stock awards     9 months 29 days    
2018 Equity Incentive Plan [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Common shares reserved for issuance under incentive plan 99,459   99,459    
Award expiration period     10 years    
2018 Equity Incentive Plan [Member] | Minimum [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
2018 Equity Incentive Plan [Member] | Minimum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     1 year    
2018 Equity Incentive Plan [Member] | Maximum [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     4 years    
2018 Equity Incentive Plan [Member] | Maximum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
2018 Equity Incentive Plan [Member] | Stock Options [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Common shares reserved for issuance under incentive plan 215,514   215,514    
Common shares reserved for options currently outstanding 116,055   116,055    
2017 Equity Incentive Plan [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award expiration period     10 years    
2017 Equity Incentive Plan [Member] | Minimum [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
2017 Equity Incentive Plan [Member] | Minimum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     1 year    
2017 Equity Incentive Plan [Member] | Maximum [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     4 years    
2017 Equity Incentive Plan [Member] | Maximum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
2017 Equity Incentive Plan [Member] | Stock Options [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Common shares reserved for issuance under incentive plan 13,156   13,156    
2010 Performance Incentive Plan [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award expiration period     10 years    
2010 Performance Incentive Plan [Member] | Minimum [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
2010 Performance Incentive Plan [Member] | Minimum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     1 year    
2010 Performance Incentive Plan [Member] | Maximum [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     4 years    
2010 Performance Incentive Plan [Member] | Maximum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
2010 Performance Incentive Plan [Member] | Stock Options [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Common shares reserved for issuance under incentive plan 490   490    
Common shares reserved for options currently outstanding 259   259    
2010 Performance Incentive Plan [Member] | Restricted Stock Unit [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Common shares reserved for awards currently outstanding 231   231