Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Property and equipment (Details)

v3.19.3.a.u2
Summary of Significant Accounting Policies - Property and equipment (Details) - Office Equipment And Furniture
12 Months Ended
Dec. 31, 2019
Minimum [Member]  
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 3 years
Maximum [Member]  
Property, Plant and Equipment [Line Items]  
Property, Plant and Equipment, Useful Life 5 years