Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity - Grants Outside of 2000 and 2017 Plans and Stockholder Rights Plan (Details)

v3.20.1
Stockholders' Equity - Grants Outside of 2000 and 2017 Plans and Stockholder Rights Plan (Details)
 12 Months Ended 43 Months Ended
Feb. 10, 2020
USD ($)
Dec. 09, 2019
$ / shares
Dec. 08, 2019
$ / shares
Sep. 04, 2019
USD ($)
$ / shares
shares
May 06, 2019
Vote
$ / shares
Feb. 04, 2019
USD ($)
$ / shares
shares
Apr. 13, 2018
$ / shares
shares
Mar. 31, 2020
USD ($)
$ / shares
shares
Mar. 31, 2019
USD ($)
$ / shares
shares
Mar. 31, 2019
USD ($)
$ / shares
shares
Jun. 07, 2018
USD ($)
Aug. 28, 2015
USD ($)
Stockholder Rights Plan                        
Common stock, par value (in dollars per share)               $ 0.001 $ 0.001 $ 0.001    
Preferred stock, par value (in dollars per share)               0.001 $ 0.001 0.001    
Offerings of Common Stock and Warrants and At-the-Market Offering Program                        
Warrants, aggregate shares | shares       440,000                
Exercise price (in dollars per share)           $ 0.001            
Initial exercise price (in dollars per share)               $ 6.12        
Deemed dividend | $                 $ 2,272,000      
Decrease the exercise price   $ 3.80 $ 8.86                  
Additional debt discount | $               $ 300,000        
Aggregate registered direct offering (in shares) | shares       580,000                
Negotiated purchase price of common stock       $ 5.00                
Negotiated purchase price of pre-funded warrant       $ 5.00                
Common stock, par value (in dollars per share)               $ 0.001 $ 0.001 $ 0.001    
Exercise price of common stock (in dollars per share)               $ 1.15        
Net proceeds from offering of common stock and warrants | $       $ 4,600,000       $ 9,959,000 $ 11,098,000      
Purchase price | $       $ 5,100,000                
Warrant Activity                        
Issuance of warrants (in shares) | shares               765,000        
Common warrants period               5 years        
Percentage of common stock               75.00%        
Aggregate registered direct offering par value (in dollars per share)       $ 0.001                
Common stock sold (in shares) | shares             380,621          
Class of Warrant or Right, Exercise Price of Warrants or Rights           $ 0.001            
Sponsorship Agreement                        
Warrant Activity                        
Sponsorship fee | $ $ 1,300,000                      
Sponsorship fee payable in cash | $ $ 700,000                      
Number of installments four                      
Value of stock issuable | $ $ 600,000                      
Payment made for sponsorship fee | $               $ 300,000        
Value of stock issued | $               $ 229,886        
Series A Warrants                        
Offerings of Common Stock and Warrants and At-the-Market Offering Program                        
Exercise price (in dollars per share)             $ 6.00          
Outstanding warrants (in shares) | shares               271,875        
Warrant Activity                        
Warrants Exercised | shares             576,000          
Class of Warrant or Right, Exercise Price of Warrants or Rights             $ 6.00          
Series A Warrants, Exercise Price 25.5                        
Offerings of Common Stock and Warrants and At-the-Market Offering Program                        
Exercise price (in dollars per share)               $ 25.50        
Issued warrants (in shares) | shares               217,875        
Warrant Activity                        
Class of Warrant or Right, Exercise Price of Warrants or Rights               $ 25.50        
Series A Warrants, Exercise Price 13.4                        
Offerings of Common Stock and Warrants and At-the-Market Offering Program                        
Initial exercise price (in dollars per share)               $ 13.40        
Issued warrants (in shares) | shares               54,000        
Series B Warrants                        
Offerings of Common Stock and Warrants and At-the-Market Offering Program                        
Outstanding warrants (in shares) | shares               0        
Common Stock Warrants                        
Offerings of Common Stock and Warrants and At-the-Market Offering Program                        
Warrants, aggregate shares | shares           404,634            
Exercise price (in dollars per share)           $ 8.86            
Issued warrants (in shares) | shares               49,891        
Deemed dividend | $               $ 87,362        
Purchase price | $           $ 150,000            
Warrant Activity                        
Value of warrants | $           $ 2,300,000            
Class of Warrant or Right, Exercise Price of Warrants or Rights           $ 8.86            
August 2015 Sales Agreement                        
Offerings of Common Stock and Warrants and At-the-Market Offering Program                        
Net proceeds from sale of the common stock, after deducting fees and other offering expenses (in dollars) | $               $ 4,000,000   $ 28,600,000    
Warrant Activity                        
Common stock sold (in shares) | shares               300,000   2,600,000    
Common stock commissions paid | $               $ 100,000   $ 800,000    
June 2018 Sales Agreement                        
Offerings of Common Stock and Warrants and At-the-Market Offering Program                        
Net proceeds from sale of the common stock, after deducting fees and other offering expenses (in dollars) | $               5,300,000        
Warrant Activity                        
Aggregate offering price for at-the-market offering program | $               $ 12,200,000        
Common stock sold (in shares) | shares               1,700,000        
Common stock commissions paid | $               $ 200,000        
Maximum | August 2015 Sales Agreement                        
Warrant Activity                        
Aggregate offering price for at-the-market offering program | $                       $ 30,000,000
Maximum | June 2018 Sales Agreement                        
Warrant Activity                        
Aggregate offering price for at-the-market offering program | $                     $ 25,000,000  
Stock options                        
Class of Stock [Line Items]                        
Options outstanding (in shares) | shares               11,249 17,499 17,499    
Portion vesting one year after the issuance date (as a percent)               25.00%        
Portion vesting on first day of each month after one year from the issuance date (as a percent)               2.083%        
Expiration term               10 years        
Vesting period               4 years        
Series B Junior Participating Preferred Stock                        
Stockholder Rights Plan                        
Preferred stock conversion basis         0.001              
Purchase price (in dollars per share)         $ 5.22              
Preferred stock dividend minimum if declared         $ 1.00              
Preferred stock rights ratio over common stock         1,000              
Number of votes per share | Vote         1,000              
Ratio of consideration received in event of conversion or exchange transaction         1,000              
Series B Junior Participating Preferred Stock | Minimum                        
Stockholder Rights Plan                        
Beneficial ownership of common stock (as a percent)         4.90%