v3.21.2
Summary of Significant Accounting Policies - Property and Equipment (Details)
9 Months Ended 12 Months Ended
Sep. 30, 2021
Dec. 31, 2020
Buildings.    
Property, Plant and Equipment [Line Items]    
Property and Equipment Useful Lives (in years) 15 years 15 years
Leasehold improvements    
Property, Plant and Equipment [Line Items]    
Property and Equipment Useful Lives (in years) 5 years 5 years
Minimum | Vehicles    
Property, Plant and Equipment [Line Items]    
Property and Equipment Useful Lives (in years) 5 years 5 years
Minimum | Equipment    
Property, Plant and Equipment [Line Items]    
Property and Equipment Useful Lives (in years) 5 years 5 years
Minimum | Office equipment    
Property, Plant and Equipment [Line Items]    
Property and Equipment Useful Lives (in years) 5 years 5 years
Maximum | Vehicles    
Property, Plant and Equipment [Line Items]    
Property and Equipment Useful Lives (in years) 10 years 10 years
Maximum | Equipment    
Property, Plant and Equipment [Line Items]    
Property and Equipment Useful Lives (in years) 7 years 7 years
Maximum | Office equipment    
Property, Plant and Equipment [Line Items]    
Property and Equipment Useful Lives (in years) 7 years 7 years