Quarterly report pursuant to Section 13 or 15(d)

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

v3.22.1
Convertible Preferred Stock and Stockholders' Equity - Warrants for common stock outstanding and exercisable (Details) - Warrant - $ / shares
 3 Months Ended 12 Months Ended
Mar. 31, 2022
Dec. 31, 2021
Exercise Price Range One    
Class of Stock [Line Items]    
Warrants Outstanding 1,647,165 3,537,965
Weighted Average Remaining Life (years) 3 years 4 months 13 days 3 years 6 months 21 days
Warrants Exercisable 1,637,165 3,527,965
Exercise Price Range One | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 1.52 $ 1.52
Exercise Price Range One | Maximum    
Class of Stock [Line Items]    
Exercise Price $ 2.61 $ 3.90
Exercise Price Range Two    
Class of Stock [Line Items]    
Warrants Outstanding 2,446,219 588,308
Weighted Average Remaining Life (years) 3 years 4 months 17 days 4 years 3 days
Warrants Exercisable 2,446,219 588,308
Exercise Price Range Two | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 3.00 $ 4.20
Exercise Price Range Two | Maximum    
Class of Stock [Line Items]    
Exercise Price $ 4.46 $ 9.80
Exercise Price Range Three    
Class of Stock [Line Items]    
Warrants Outstanding 32,889 92,963
Weighted Average Remaining Life (years) 2 years 10 months 28 days 1 year 21 days
Warrants Exercisable 32,889 92,963
Exercise Price Range Three | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 6.40 $ 15.80
Exercise Price Range Three | Maximum    
Class of Stock [Line Items]    
Exercise Price $ 9.80 $ 17.50
Exercise Price Range Four    
Class of Stock [Line Items]    
Warrants Outstanding 92,940 222,807
Weighted Average Remaining Life (years) 11 months 15 days 1 year 1 month 17 days
Warrants Exercisable 92,940 222,807
Exercise Price Range Four | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 15.80 $ 24.80
Exercise Price Range Four | Maximum    
Class of Stock [Line Items]    
Exercise Price $ 17.50 $ 99.00
Exercise Price Range Five    
Class of Stock [Line Items]    
Warrants Outstanding 255,090 47,678
Weighted Average Remaining Life (years) 10 months 17 days 10 months 24 days
Warrants Exercisable 255,090 47,678
Exercise Price Range Five | Minimum    
Class of Stock [Line Items]    
Exercise Price $ 24.80 $ 108.00
Exercise Price Range Five | Maximum    
Class of Stock [Line Items]    
Exercise Price 125.00 125.00
Exercise Price Range Six    
Class of Stock [Line Items]    
Exercise Price $ 6.92 $ 7.26
Warrants Outstanding 4,474,303 4,489,721
Weighted Average Remaining Life (years) 3 years 2 months 12 days 3 years 5 months 8 days
Warrants Exercisable 4,464,303 4,479,721