Quarterly report pursuant to Section 13 or 15(d)

Capitalization and Equity Structure - Narrative (Details)

v3.23.1
Capitalization and Equity Structure - Narrative (Details)
$ / shares in Units, $ in Thousands
 1 Months Ended 2 Months Ended 3 Months Ended
Jun. 08, 2020
Oct. 30, 2020
USD ($)
$ / shares
Jun. 30, 2020
$ / shares
shares
Dec. 31, 2019
$ / shares
shares
May 30, 2019
Feb. 28, 2021
$ / shares
shares
Mar. 31, 2023
USD ($)
$ / shares
shares
Mar. 31, 2022
shares
Dec. 31, 2022
shares
Dec. 31, 2021
shares
May 31, 2019
$ / shares
shares
Class of Stock [Line Items]                      
Common stock, shares authorized (in shares)             141,429,000   141,429,000    
Preferred Stock, shares authorized (in shares)             10,000,000   10,000,000    
Common stock, shares outstanding (in shares)             13,342,000   13,203,000    
Common stock, shares issued (in shares)             13,342,000   13,203,000    
Preferred stock, shares outstanding (in shares)             0   0    
Preferred stock, shares issued (in shares)             0   0    
Number warrants called (in shares)             1,240,000   1,240,000    
Warrants issued (in shares)             0        
Exercised (in shares)             0        
At-the-market offering                      
Class of Stock [Line Items]                      
Number warrants called (in shares)             0 0      
Sale of shares (in dollars per share) | $ / shares   $ 6.75                  
Value of shares sold | $   $ 7,500                  
Common stock                      
Class of Stock [Line Items]                      
Common stock, shares outstanding (in shares)             13,342,000 12,844,000 13,203,000 12,693,000  
Warrants exercised (in shares)             0        
Common stock | At-the-market offering                      
Class of Stock [Line Items]                      
Available for future offerings | $             $ 6,668        
2021 Warrants                      
Class of Stock [Line Items]                      
Number warrants called (in shares)             273,000   273,000    
Exercise price (in dollars per share) | $ / shares           $ 12.81 $ 12.81        
Warrants issued (in shares)           273,000 0        
Class of warrant or right expiration period           5 years 5 years        
Duration of put option           30 days          
Put option pay period           5 days          
Exercised (in shares)             0        
June 2020 Warrants                      
Class of Stock [Line Items]                      
Exercise price (in dollars per share) | $ / shares     $ 5.18                
Class of warrant or right expiration period             5 years 6 months        
June 2020 Investor Warrants                      
Class of Stock [Line Items]                      
Number warrants called (in shares)             127,000   127,000    
Exercise price (in dollars per share) | $ / shares     $ 5.18       $ 5.18        
Warrants issued (in shares)             0        
Class of warrant or right expiration period             5 years 6 months        
Duration of put option     30 days                
Exercised (in shares)             0        
Reverse stock split             0.067        
June 2020 Investor Warrants | Common stock | Direct offering                      
Class of Stock [Line Items]                      
Number warrants called (in shares)     874,000                
June 2020 Placement Agent Warrants                      
Class of Stock [Line Items]                      
Number warrants called (in shares)             39,000   39,000    
Exercise price (in dollars per share) | $ / shares             $ 5.64        
Warrants issued (in shares)     122,000       0        
Class of warrant or right expiration period             5 years        
Exercised (in shares)             0        
December 2019 Warrants                      
Class of Stock [Line Items]                      
Number warrants called (in shares)       556,000     556,000   556,000    
Exercise price (in dollars per share) | $ / shares       $ 8.10     $ 8.10        
Warrants issued (in shares)             0        
Class of warrant or right expiration period       5 years     5 years        
Duration of put option       30 days              
Put option pay period       5 days              
Exercised (in shares)             0        
December 2019 Placement Agent Warrants                      
Class of Stock [Line Items]                      
Number warrants called (in shares)       52,000     52,000   52,000    
Exercise price (in dollars per share) | $ / shares       $ 8.44     $ 8.44        
Warrants issued (in shares)             0        
Class of warrant or right expiration period             5 years        
Exercised (in shares)             0        
May 2019 Warrants                      
Class of Stock [Line Items]                      
Number warrants called (in shares)             193,000   193,000   444,000
Exercise price (in dollars per share) | $ / shares     $ 3.52       $ 3.52       $ 3.52
Warrants issued (in shares)             0        
Class of warrant or right expiration period             5 years        
Duration of put option         90 days            
Put option pay period 5 days                    
Exercised (in shares)             0        
May 2019 Warrants | Common stock | Direct offering                      
Class of Stock [Line Items]                      
Sale of shares (in dollars per share) | $ / shares     $ 4.51