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
 9 Months Ended 12 Months Ended
Sep. 30, 2021
Dec. 31, 2020
Exercise Price Range One    
Class of Stock [Line Items]    
Warrants Outstanding 4,053,384 6,884,216
Weighted Average Remaining Life (years) 3 years 10 months 9 days 4 years 6 months 18 days
Warrants Exercisable 4,038,384 6,869,216
Exercise Price Range One | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 2.32 $ 2.32
Exercise Price Range One | Maximum    
Class of Stock [Line Items]    
Exercise Price $ 4.46 $ 3.90
Exercise Price Range Two    
Class of Stock [Line Items]    
Warrants Outstanding 32,889 32,889
Weighted Average Remaining Life (years) 3 years 4 months 28 days 4 years 1 month 24 days
Warrants Exercisable 32,889 32,889
Exercise Price Range Two | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 6.40 $ 6.40
Exercise Price Range Two | Maximum    
Class of Stock [Line Items]    
Exercise Price $ 9.80 $ 9.80
Exercise Price Range Three    
Class of Stock [Line Items]    
Warrants Outstanding 93,562 93,562
Weighted Average Remaining Life (years) 1 year 3 days 1 year 9 months 3 days
Warrants Exercisable 93,562 93,562
Exercise Price Range Three | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 15.80 $ 15.80
Exercise Price Range Three | Maximum    
Class of Stock [Line Items]    
Exercise Price $ 17.50 $ 17.50
Exercise Price Range Four    
Class of Stock [Line Items]    
Warrants Outstanding 222,807 230,571
Weighted Average Remaining Life (years) 1 year 4 months 17 days 11 months 26 days
Warrants Exercisable 222,807 230,571
Exercise Price Range Four | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 24.80 $ 24.80
Exercise Price Range Four | Maximum    
Class of Stock [Line Items]    
Exercise Price $ 99.00 $ 99.00
Exercise Price Range Five    
Class of Stock [Line Items]    
Warrants Outstanding 72,782 72,864
Weighted Average Remaining Life (years) 10 months 13 days 1 year 7 months 6 days
Warrants Exercisable 72,782 72,864
Exercise Price Range Five | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 108.00 $ 108.00
Exercise Price Range Five | Maximum    
Class of Stock [Line Items]    
Exercise Price 125.00 207.00
Exercise Price Range Six    
Class of Stock [Line Items]    
Exercise Price $ 7.88 $ 5.81
Warrants Outstanding 4,475,424 7,314,102
Weighted Average Remaining Life (years) 3 years 7 months 28 days 4 years 6 months 14 days
Warrants Exercisable 4,460,424 7,299,102