Quarterly report pursuant to Section 13 or 15(d)

Equity - Narrative (Details)

v3.10.0.1
Equity - Narrative (Details)
1 Months Ended 2 Months Ended 3 Months Ended 9 Months Ended 12 Months Ended
Jun. 22, 2018
USD ($)
$ / shares
shares
Feb. 16, 2018
USD ($)
$ / shares
shares
Sep. 15, 2017
USD ($)
Jul. 29, 2017
warrant
$ / shares
shares
Oct. 31, 2018
USD ($)
$ / shares
shares
Apr. 30, 2018
$ / shares
shares
Jan. 31, 2018
$ / shares
shares
Aug. 31, 2017
$ / shares
Jul. 31, 2017
$ / shares
Jan. 31, 2017
USD ($)
$ / shares
shares
Aug. 31, 2017
shares
Sep. 30, 2018
USD ($)
shares
Sep. 30, 2018
USD ($)
$ / shares
shares
Dec. 31, 2017
shares
Apr. 06, 2018
shares
Feb. 09, 2017
shares
May 02, 2016
shares
Class of Stock [Line Items]                                  
Shares authorized                       80,000,000 80,000,000       80,000,000
Preferred stock authorized (in shares)                       5,000,000 5,000,000 5,000,000     5,000,000
Common stock authorized (in shares)                       75,000,000 75,000,000 75,000,000     75,000,000
Preferred stock, shares issued                       0 0 0      
Options exercised (in shares)                         0        
Additional shares available for purchase                         1,429,000        
Exercise price (in dollars per share) | $ / shares                         $ 1.81        
Shares granted, contractual term                         8 years 8 months 8 days 9 years 25 days      
Options granted, aggregate fair value | $                         $ 1,800,000        
Unrecognized compensation cost, net of estimated forfeitures, related to the Company's non-vested equity awards | $                       $ 3,400,000 $ 3,400,000        
Weighted average period of expected recognition of compensation cost (in years)                         3 years 14 days        
Exercise price per warrant (in dollars per share) | $ / shares   $ 2.80                              
Warrant term   5 years                              
Proceeds from issuance or sale of equity | $   $ 9,000,000.0                              
Net proceeds from registered offering | $   $ 8,200,000                              
Warrants, initial exercise period   6 months                              
Securities Purchase Agreement                                  
Class of Stock [Line Items]                                  
Class of warrants, aggregate amounts (in shares)   2,273,700                              
Proceeds from issuance or sale of equity | $   $ 9,000,000.0                              
June 2018 Registered Direct Offering                                  
Class of Stock [Line Items]                                  
Exercise price per warrant (in dollars per share) | $ / shares $ 2.02                                
Expiration period                         5 years        
Warrant term 5 years                                
Proceeds from issuance or sale of equity | $ $ 2,300,000                                
Number of shares sold 1,092,636                                
Sale of common stock (in dollars per share) | $ / shares $ 2.105                                
Warrants, initial exercise period 6 months                                
Common stock offered for each warrant (in shares) 0.65                                
2015 Stock Plan                                  
Class of Stock [Line Items]                                  
Total number of underlying shares of common stock available under 2015 Stock Plan                             4,500,000    
Science Advisory Board Member                                  
Class of Stock [Line Items]                                  
Additional shares available for purchase             10,000                    
Exercise price (in dollars per share) | $ / shares             $ 1.89                    
Shares granted, contractual term             10 years                    
Science Advisory Board Member | Employee Stock Option                                  
Class of Stock [Line Items]                                  
Vesting period             4 years                    
Science Advisory Board                                  
Class of Stock [Line Items]                                  
Additional shares available for purchase                   20,000              
Exercise price (in dollars per share) | $ / shares                   $ 2.31              
Vesting period                   4 years              
Term of awards                   10 years              
Aggregate fair value of options granted | $                   $ 35,196              
Board and Management                                  
Class of Stock [Line Items]                                  
Additional shares available for purchase                     140,000            
Exercise price (in dollars per share) | $ / shares               $ 2.88 $ 1.87                
Vesting period                     4 years            
Term of awards                     10 years            
Aggregate fair value of options granted | $                         $ 200,000        
The Warrants                                  
Class of Stock [Line Items]                                  
Period of agreement       12 months                          
Number of warrants issued | warrant       2                          
Vesting period       12 months                          
Expiration period       5 years                          
Stock compensation expense | $                       $ 37,715 $ 109,240        
GSK Consulting Agreement Warrant One                                  
Class of Stock [Line Items]                                  
Class of warrants, aggregate amounts (in shares)       100,000                          
Exercise price per warrant (in dollars per share) | $ / shares       $ 2.41                          
GSK Consulting Agreement Warrant Two                                  
Class of Stock [Line Items]                                  
Class of warrants, aggregate amounts (in shares)       50,000                          
Exercise price per warrant (in dollars per share) | $ / shares       $ 3.00                          
Consulting Agreement Warrant Three                                  
Class of Stock [Line Items]                                  
Class of warrants, aggregate amounts (in shares)           100,000                      
Exercise price per warrant (in dollars per share) | $ / shares           $ 3.00                      
Warrant term           3 years                      
Agents | At Market Issuance Sales Agreement                                  
Class of Stock [Line Items]                                  
Commissions paid, percentage of gross proceeds     3.00%                            
Common Stock                                  
Class of Stock [Line Items]                                  
Class of warrants, aggregate amounts (in shares)   2,145,000                              
Common stock offered for each warrant (in shares)                               1  
Common Stock | Securities Purchase Agreement                                  
Class of Stock [Line Items]                                  
Class of warrants, aggregate amounts (in shares)   2,145,000                              
Number of shares sold   4,290,000                              
Sale of common stock (in dollars per share) | $ / shares   $ 2.10                              
Common Stock | June 2018 Registered Direct Offering                                  
Class of Stock [Line Items]                                  
Class of warrants, aggregate amounts (in shares) 710,212                                
Common Stock | Agents | At Market Issuance Sales Agreement | Maximum                                  
Class of Stock [Line Items]                                  
Aggregate sales price | $     $ 13,000,000.0                            
Subsequent Event | Former Employee                                  
Class of Stock [Line Items]                                  
Options exercised (in shares)         25,000                        
Price per share of options exercised | $ / shares         $ 0.20                        
Proceeds from stock options exercised | $         $ 5,000