Quarterly report pursuant to Section 13 or 15(d)

Stock Based Compensation (Details)

v3.19.3
Stock Based Compensation (Details)
 1 Months Ended 3 Months Ended 9 Months Ended 12 Months Ended
Jan. 01, 2019
$ / shares
shares
May 18, 2016
shares
Apr. 05, 2016
USD ($)
shares
Aug. 31, 2019
shares
Apr. 30, 2019
shares
May 31, 2018
shares
Sep. 30, 2019
USD ($)
day
$ / shares
shares
Jun. 30, 2019
USD ($)
shares
Sep. 30, 2018
USD ($)
Sep. 30, 2019
USD ($)
$ / shares
shares
Sep. 30, 2018
USD ($)
Dec. 31, 2018
$ / shares
shares
Annual share reserve increase (as a percent)                   4.00%    
Total stock-based compensation | $             $ 818,793   $ 945,133 $ 1,942,196 $ 1,796,387  
Research and development                        
Total stock-based compensation | $             176,261   32,202 354,347 64,077  
General and administrative                        
Total stock-based compensation | $             473,905   843,122 1,139,241 1,599,703  
Sales and marketing                        
Total stock-based compensation | $             168,627   69,809 448,608 132,607  
Service Based Options                        
Total stock-based compensation | $             $ 600,000     $ 1,600,000    
Option Activity, Number of shares                        
Balance, beginning of period (in shares) 3,746,597                 3,746,597    
Granted (in shares)                   2,618,264    
Options exercises in period (in shares)                   (75,178)    
Forfeitures (in shares)                   (902,767)    
Expired (in shares)                   (389,792)    
Balance, end of period (in shares)             4,997,124     4,997,124   3,746,597
Exercisable (in shares)             2,155,081     2,155,081    
Option Activity, Weighted-average exercise price                        
Beginning of period (in dollars per share) | $ / shares $ 4.16                 $ 4.16    
Granted (in dollars per share) | $ / shares                   5.71    
Exercised (in dollars per share) | $ / shares                   3.44    
Forfeitures (in dollars per share) | $ / shares                   5.16    
Expired (in dollars per share) | $ / shares                   5.03    
End of period (in dollars per share) | $ / shares             $ 4.74     4.74   $ 4.16
Exercisable (in dollars per share) | $ / shares             $ 4.36     $ 4.36    
Option Activity, Fair value of options granted                        
Grant date fair value of options granted | $             $ 8,076,475     $ 8,076,475    
Grant date fair value of options forfeited | $             2,640,665     2,640,665    
Weighted average grant date fair value of options expired | $             992,343     $ 992,343    
Option Activity, Weighted-average remaining contractual term (in years)                        
Balance                   8 years 2 months 25 days   7 years 9 months 18 days
Exercisable                   6 years 10 months 24 days    
Aggregate intrinsic value | $             1,300,000     $ 1,300,000    
Exercisable aggregate intrinsic value | $             $ 900,000     900,000    
Fair value of options vested in period | $                   $ 1,300,000    
Per share weighted average fair value of options granted (in dollars per share) | $ / shares                   $ 3.08    
Options vested (in shares)                   622,583    
Weighted average exercise price (in dollars per share) | $ / shares             $ 3.54     $ 3.54    
Compensation not yet recognized | $             $ 7,000,000     $ 7,000,000    
Period for recognition                   3 years    
Fair value assumptions                        
Expected annual dividend yield                   0.00%    
Expected volatility                   55.00%    
Stock Options With Market Based Vesting Conditions                        
Total stock-based compensation | $             $ 100,000       $ (200,000)  
Option Activity, Number of shares                        
Balance, beginning of period (in shares) 500,000                 500,000    
Granted (in shares)                   300,000    
Options exercises in period (in shares)                   0    
Forfeitures (in shares)                   (500,000)    
Balance, end of period (in shares)             300,000     300,000   500,000
Exercisable (in shares)             0     0    
Option Activity, Weighted-average exercise price                        
Beginning of period (in dollars per share) | $ / shares $ 4.24                 $ 4.24    
Granted (in dollars per share) | $ / shares                   4.98    
Forfeitures (in dollars per share) | $ / shares                   4.24    
End of period (in dollars per share) | $ / shares             $ 4.98     $ 4.98   $ 4.24
Option Activity, Weighted-average remaining contractual term (in years)                        
Balance                   9 years 7 months 25 days   9 years 2 months 27 days
Aggregate intrinsic value | $             $ 0     $ 0    
Compensation not yet recognized | $             900,000     $ 900,000    
Period for recognition                   2 years 2 months 12 days    
Fair value assumptions                        
Expected annual dividend yield                   0.00%    
Expected volatility                   60.00%    
Expected term of options (in years)                   10 years    
Risk-free interest rate                   2.32%    
Restricted Stock Awards                        
Award vesting period                   4 years    
Total stock-based compensation | $             100,000     $ 400,000    
Compensation not yet recognized | $             $ 1,300,000     $ 1,300,000    
Option Activity, Weighted-average remaining contractual term (in years)                        
Period for recognition                   2 years 7 months 6 days    
Non-vested RSUs Outstanding                        
RSAs granted (in shares)                   295,000    
RSAs vested (in shares)                   172,500    
RSAs forfeited (in shares)                   (300,000)    
Ending balance of Non-vested RSAs (in shares)             267,500     267,500   445,000
Weighted average grant date fair value                        
Nonvested RSAs weighted average grant date fair value (in dollars per share) | $ / shares                       $ 4.27
Nonvested RSAs grants in period weighted average grant date fair value (in dollars per share) | $ / shares                   $ 4.98    
RSAs vested in period weighted average grant date fair value (in dollars per share) | $ / shares                   4.52    
Nonvested RSAs forfeitures weighted average grant date fair value (in dollars per share) | $ / shares                   $ 4.24    
Employee Stock Purchase Plan (ESPP)                        
Total stock-based compensation | $             $ 42,278     $ 129,963    
Minimum | Service Based Options                        
Fair value assumptions                        
Expected term of options (in years)                   5 years    
Risk-free interest rate                   1.47%    
Maximum | Service Based Options                        
Fair value assumptions                        
Expected term of options (in years)                   6 years 3 months    
Risk-free interest rate                   2.59%    
2016 Plan                        
Increase in number of shares reserved for issuance (in shares)   600,000       1,400,000.0            
Common stock remaining for future issuance (in shares)             1,963,869     1,963,869    
2016 Plan | Equity Option                        
Award expiration period                   10 years    
2016 Second Amended Plan                        
Increase in number of shares reserved for issuance (in shares)       850,000                
2015 Plan                        
Common stock remaining for future issuance (in shares)   464,476                    
Employee Stock Purchase Plan (ESPP)                        
Common stock remaining for future issuance (in shares)             1,148,085     1,148,085    
Weighted average grant date fair value                        
Percentage of fair market value on the lower of first day or last day of the offering period at which employees may purchase stock under the ESPP     85.00%                  
Maximum portion of earning an employee may contribute to the ESPP Plan     15.00%                  
Maximum annual amount of fair market value of the Company's common stock that a participant may accrue the rights to purchase | $     $ 25,000                  
Shares of common stock for future issuance (in shares)     500,000                  
Automatic increase to shares authorized as percentage of outstanding stock at end of preceding year     1.00%                  
Increase in shares available (in shares) 408,042                      
Employee | 2016 Plan | Minimum | Equity Option                        
Award vesting period                   3 years    
Employee | 2016 Plan | Maximum | Equity Option                        
Award vesting period                   4 years    
Director | 2016 Plan | Equity Option                        
Award vesting period                   3 years    
Terminated Executive                        
Total stock-based compensation | $                 $ 300,000 $ 300,000    
Terminated Executive | Option And Non Option Awards                        
Forfeitures (in shares)         1,489,583              
Terminated Executive | Service Based Options                        
Option Activity, Number of shares                        
Forfeitures (in shares)         (689,583)              
Terminated Executive | Stock Options With Market Based Vesting Conditions                        
Option Activity, Number of shares                        
Forfeitures (in shares)         (500,000)              
Terminated Executive | Restricted Stock Awards                        
Total stock-based compensation | $               $ (500,000)        
Requisite service period         2 years 9 months 18 days              
Non-vested RSUs Outstanding                        
RSAs forfeited (in shares)         (300,000)              
Board of Directors Chairman | Stock Options With Market Based Vesting Conditions                        
Option Activity, Number of shares                        
Granted (in shares)             300,000          
Option Activity, Weighted-average exercise price                        
Granted (in dollars per share) | $ / shares             $ 4.98          
Board of Directors Chairman | Restricted Stock Awards                        
Non-vested RSUs Outstanding                        
RSAs granted (in shares)               250,000        
RSAs vested (in shares)               50,000        
Tranche One | Board of Directors Chairman | Stock Options With Market Based Vesting Conditions                        
Award vesting percentage             33.33%          
Weighted average grant date fair value                        
Number of days above threshold to trigger vesting | day             3          
Tranche One | Board of Directors Chairman | Restricted Stock Awards                        
Award vesting percentage                   33.33%    
Tranche One | Board of Directors Chairman | Minimum                        
Option Activity, Weighted-average exercise price                        
Share price (in dollars per share) | $ / shares             $ 8.00     $ 8.00    
Tranche Two | Board of Directors Chairman | Stock Options With Market Based Vesting Conditions                        
Award vesting percentage             33.33%          
Weighted average grant date fair value                        
Number of days above threshold to trigger vesting | day             3          
Tranche Two | Board of Directors Chairman | Restricted Stock Awards                        
Award vesting percentage                   33.33%    
Tranche Two | Board of Directors Chairman | Minimum                        
Option Activity, Weighted-average exercise price                        
Share price (in dollars per share) | $ / shares             $ 10.50     $ 10.50    
Tranche Three | Board of Directors Chairman | Stock Options With Market Based Vesting Conditions                        
Award vesting percentage             33.33%          
Weighted average grant date fair value                        
Number of days above threshold to trigger vesting | day             3          
Tranche Three | Board of Directors Chairman | Restricted Stock Awards                        
Award vesting percentage                   33.33%    
Tranche Three | Board of Directors Chairman | Minimum                        
Option Activity, Weighted-average exercise price                        
Share price (in dollars per share) | $ / shares             $ 13.00     $ 13.00