Annual report pursuant to Section 13 and 15(d)

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

v3.20.1
Convertible Preferred Stock and Stockholders' Equity - Warrants for common stock outstanding and exercisable (Details) - Warrant [Member] - $ / shares
 12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Class of Stock [Line Items]    
Exercise Price $ 3.58  
Warrants Outstanding 7,937,094 2,543,577
Remaining Life (years) 3 years 3 years 6 months 29 days
Warrants Exercisable 7,739,822 2,543,577
Exercise Price Range One [Member]    
Class of Stock [Line Items]    
Exercise Price $ 2.00  
Warrants Outstanding 2,653,956 275,000
Remaining Life (years) 2 years 11 months 12 days 4 years 3 months 4 days
Warrants Exercisable 2,456,684 97,778
Exercise Price Range One [Member] | Minimum [Member]    
Class of Stock [Line Items]    
Exercise Price $ 0.79  
Exercise Price Range One [Member] | Maximum [Member]    
Class of Stock [Line Items]    
Exercise Price $ 2.18  
Exercise Price Range Two [Member]    
Class of Stock [Line Items]    
Warrants Outstanding 3,638,911 5,522,720
Remaining Life (years) 2 years 11 months 9 days 4 years 2 months 16 days
Warrants Exercisable 3,638,911 5,522,720
Exercise Price Range Two [Member] | Minimum [Member]    
Class of Stock [Line Items]    
Exercise Price $ 3.00 $ 3.00
Exercise Price Range Two [Member] | Maximum [Member]    
Class of Stock [Line Items]    
Exercise Price $ 4.00 $ 4.00
Exercise Price Range Three [Member]    
Class of Stock [Line Items]    
Warrants Outstanding 187,767 298,882
Remaining Life (years) 1 year 4 months 28 days 2 years 8 months 23 days
Warrants Exercisable 187,767 298,882
Exercise Price Range Three [Member] | Minimum [Member]    
Class of Stock [Line Items]    
Exercise Price $ 4.50 $ 4.50
Exercise Price Range Three [Member] | Maximum [Member]    
Class of Stock [Line Items]    
Exercise Price $ 4.95 4.95
Exercise Price Range Four Member [Member]    
Class of Stock [Line Items]    
Warrants Outstanding 1,454,826  
Remaining Life (years) 2 years 7 months 13 days  
Warrants Exercisable 1,454,826  
Exercise Price Range Four Member [Member] | Minimum [Member]    
Class of Stock [Line Items]    
Exercise Price $ 5.40 5.40
Exercise Price Range Four Member [Member] | Maximum [Member]    
Class of Stock [Line Items]    
Exercise Price 6.25 6.25
Exercise Price Range Five Member [Member]    
Class of Stock [Line Items]    
Exercise Price $ 10.35 $ 10.35
Warrants Outstanding 1,634 1,634
Remaining Life (years) 1 year 3 months 11 days 2 years 3 months 11 days
Warrants Exercisable 1,634 1,634
Exercise Price Range Six [Member]    
Class of Stock [Line Items]    
Exercise Price   $ 3.85
Warrants Outstanding   8,641,813
Remaining Life (years)   3 years 11 months 19 days
Warrants Exercisable   8,464,591