Quarterly report pursuant to Section 13 or 15(d)

Convertible Preferred Stock and Stockholders' Equity (Deficit) - Warrants for common stock outstanding and exercisable (Details)

v3.21.2
Convertible Preferred Stock and Stockholders' Equity (Deficit) - Warrants for common stock outstanding and exercisable (Details) - Warrant - $ / shares
 6 Months Ended 12 Months Ended
Jun. 30, 2021
Dec. 31, 2020
Exercise Price Range One [Member]    
Class of Stock [Line Items]    
Warrants Outstanding 4,072,384 6,884,216
Remaining Life (years) 4 years 1 month 9 days 4 years 6 months 18 days
Warrants Exercisable 4,057,384 6,869,216
Exercise Price Range One [Member] | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 2.32 $ 2.32
Exercise Price Range One [Member] | Maximum    
Class of Stock [Line Items]    
Exercise Price $ 4.46 $ 3.90
Exercise Price Range Two [Member]    
Class of Stock [Line Items]    
Warrants Outstanding 32,889 32,889
Remaining Life (years) 3 years 7 months 28 days 4 years 1 month 24 days
Warrants Exercisable 32,889 32,889
Exercise Price Range Two [Member] | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 6.40 $ 6.40
Exercise Price Range Two [Member] | Maximum    
Class of Stock [Line Items]    
Exercise Price $ 9.80 $ 9.80
Exercise Price Range Three [Member]    
Class of Stock [Line Items]    
Warrants Outstanding 93,562 93,562
Remaining Life (years) 1 year 3 months 7 days 1 year 9 months 3 days
Warrants Exercisable 93,562 93,562
Exercise Price Range Three [Member] | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 15.80 $ 15.80
Exercise Price Range Three [Member] | Maximum    
Class of Stock [Line Items]    
Exercise Price $ 17.50 $ 17.50
Exercise Price Range Four Member [Member]    
Class of Stock [Line Items]    
Warrants Outstanding 225,307 230,571
Remaining Life (years) 1 year 7 months 6 days 11 months 26 days
Warrants Exercisable 225,307 230,571
Exercise Price Range Four Member [Member] | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 24.80 $ 24.80
Exercise Price Range Four Member [Member] | Maximum    
Class of Stock [Line Items]    
Exercise Price $ 99.00 $ 99.00
Exercise Price Range Five Member [Member]    
Class of Stock [Line Items]    
Warrants Outstanding 72,782 72,864
Remaining Life (years) 1 year 1 month 13 days 1 year 7 months 6 days
Warrants Exercisable 72,782 72,864
Exercise Price Range Five Member [Member] | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 108.00 $ 108.00
Exercise Price Range Five Member [Member] | Maximum    
Class of Stock [Line Items]    
Exercise Price 125.00 207.00
Exercise Price Range Six [Member]    
Class of Stock [Line Items]    
Exercise Price $ 7.90 $ 5.81
Warrants Outstanding 4,496,924 7,314,102
Remaining Life (years) 3 years 10 months 28 days 4 years 6 months 14 days
Warrants Exercisable 4,481,924 7,299,102