XML 41 R31.htm IDEA: XBRL DOCUMENT v3.21.1
Preferred Stock and Convertible Preferred Stock (Details) - USD ($)
Mar. 31, 2021
Dec. 31, 2020
Preferred Non-Convertible Stock    
Class of Stock [Line Items]    
Preferred stock, par value (in dollars per share) $ 0.001 $ 0.001
Preferred stock, shares authorized (in shares) 5,000,000 5,000,000
Preferred stock, shares issued (in shares) 0 0
Value of preferred stock issued $ 0 $ 0
Preferred stock, shares outstanding (in shares) 0 0
Series B Convertible Preferred Stock    
Class of Stock [Line Items]    
Preferred stock, par value (in dollars per share) $ 0.001 $ 0.001
Preferred stock, shares issued (in shares) 200 200
Value of preferred stock issued $ 1 $ 1
Preferred stock, shares designated (in shares) 147,000 147,000
Preferred stock, shares outstanding (in shares) 200 200
Series F Convertible Preferred Stock    
Class of Stock [Line Items]    
Preferred stock, par value (in dollars per share) $ 0.001 $ 0.001
Preferred stock, shares issued (in shares) 0 0
Value of preferred stock issued $ 0 $ 0
Preferred stock, shares designated (in shares) 10,621 10,621
Preferred stock, shares outstanding (in shares) 0 0
Series D Convertible Preferred Stock    
Class of Stock [Line Items]    
Preferred stock, par value (in dollars per share) $ 0.001 $ 0.001
Preferred stock, shares issued (in shares) 0 0
Value of preferred stock issued $ 0 $ 0
Preferred stock, shares designated (in shares) 21,300 21,300
Preferred stock, shares outstanding (in shares) 0 0
Series E Convertible Preferred Stock    
Class of Stock [Line Items]    
Preferred stock, par value (in dollars per share) $ 0.001 $ 0.001
Preferred stock, shares issued (in shares) 0 0
Value of preferred stock issued $ 0 $ 0
Preferred stock, shares designated (in shares) 7,000 7,000
Preferred stock, shares outstanding (in shares) 0 0