Annual report pursuant to Section 13 and 15(d)

Commitments and contingencies - Operating Lease Obligations (Details)

v3.20.1
Commitments and contingencies - Operating Lease Obligations (Details) - USD ($)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Office space and warehouse facilities    
Operating Leased Assets [Line Items]    
Lease expense $ 744,781 $ 755,579