Quarterly report pursuant to Section 13 or 15(d)

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

v3.19.2
Preferred Stock and Stockholders' Equity - Warrants for common stock outstanding and exercisable (Details) - Warrant [Member]
 6 Months Ended
Jun. 30, 2019
$ / shares
shares
Class of Stock [Line Items]  
Exercise Price | $ / shares $ 3.69
Warrants Outstanding 9,060,003
Remaining Life (years) 3 years 6 months 11 days
Warrants Exercisable 8,731,915
Exercise Price Range One [Member]  
Class of Stock [Line Items]  
Warrants Outstanding 693,190
Remaining Life (years) 4 years 3 days
Warrants Exercisable 365,102
Exercise Price Range Two [Member]  
Class of Stock [Line Items]  
Warrants Outstanding 5,522,720
Remaining Life (years) 3 years 8 months 19 days
Warrants Exercisable 5,522,720
Exercise Price Range Two [Member] | Minimum [Member]  
Class of Stock [Line Items]  
Exercise Price | $ / shares $ 3.00
Exercise Price Range Two [Member] | Maximum [Member]  
Class of Stock [Line Items]  
Exercise Price | $ / shares $ 4.00
Exercise Price Range Three [Member]  
Class of Stock [Line Items]  
Warrants Outstanding 298,882
Remaining Life (years) 2 years 5 months 26 days
Warrants Exercisable 298,882
Exercise Price Range Three [Member] | Minimum [Member]  
Class of Stock [Line Items]  
Exercise Price | $ / shares $ 4.50
Exercise Price Range Three [Member] | Maximum [Member]  
Class of Stock [Line Items]  
Exercise Price | $ / shares $ 4.95
Exercise Price Range Four Member [Member]  
Class of Stock [Line Items]  
Warrants Outstanding 2,543,577
Remaining Life (years) 3 years 29 days
Warrants Exercisable 2,543,577
Exercise Price Range Four Member [Member] | Minimum [Member]  
Class of Stock [Line Items]  
Exercise Price | $ / shares $ 5.40
Exercise Price Range Four Member [Member] | Maximum [Member]  
Class of Stock [Line Items]  
Exercise Price | $ / shares 6.25
Exercise Price Range Five Member [Member]  
Class of Stock [Line Items]  
Exercise Price | $ / shares $ 10.35
Warrants Outstanding 1,634
Remaining Life (years) 2 years 14 days
Warrants Exercisable 1,634