v3.19.3
Convertible Preferred Stock and Stockholders’ Equity (Deficit) - Common Stock Narrative (Details) - USD ($)
 1 Months Ended 3 Months Ended 9 Months Ended
Mar. 31, 2019
Sep. 30, 2019
Jun. 30, 2019
Mar. 31, 2019
Sep. 30, 2018
Jun. 30, 2018
Mar. 31, 2018
Sep. 30, 2019
Sep. 30, 2018
Dec. 31, 2018
Aug. 23, 2018
Class of Stock [Line Items]                      
Common stock, shares authorized (shares)   200,000,000           200,000,000   200,000,000 200,000,000
Common stock, par value (USD per share)   $ 0.0001           $ 0.0001   $ 0.0001 $ 0.0001
Preferred stock, shares authorized (shares)                     10,000,000
Preferred stock, par value (USD per share)                     $ 0.0001
Common stock, shares issued (shares)   10,897,522           10,897,522   10,055,072  
Common stock, shares outstanding (shares)   10,897,522           10,897,522   10,055,072  
Proceeds from option exercises               $ 65,060 $ 3,499    
Proceeds from sale of common stock, net of offering costs               $ 2,409,593 $ 0    
Purchase Agreement                      
Class of Stock [Line Items]                      
Value of shares to be sold to Aspire $ 10,000,000                    
Maximum percentage owned by Aspire 19.99%                    
Number of shares issued (in shares) 272,479                    
Price per share (USD per share)   $ 3.67           $ 3.67      
Proceeds from sale of common stock, net of offering costs $ 1,000,000                    
Value of additional shares to be sold to Aspire $ 9,000,000                    
Commitment period 30 months                    
Shares issued as issuance costs (in shares) 69,444                    
Common Stock                      
Class of Stock [Line Items]                      
Share issued exercise options (shares)   0 8,526 41,521 1,068 551 237 50,047 1,856    
Proceeds from option exercises         $ 1,116     $ 65,060 $ 3,499