Annual report pursuant to Section 13 and 15(d)

Warrant derivative liability, Fair value measurements and valuation techniques (Details)

v3.20.1
Warrant derivative liability, Fair value measurements and valuation techniques (Details) - Warrant [Member]
Dec. 31, 2019
$ / shares
May 06, 2019
$ / shares
Stock Price [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
Derivative liability 2.70 6.00
Exercise Price [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
Derivative liability 1.62 3.90
Expected Remaining Term (in Years) [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
Derivative liability 0.95 1.60
Expected Remaining Term (in Years) [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
Derivative liability 1.02 1.68
Volatility [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
Derivative liability 0.69 0.64
Risk-free Interest Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
Derivative liability 0.0160 0.0239