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Concentration of Risks - Additional Information (Details) - Customer Concentration Risk
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Total revenue    
Concentration Risk [Line Items]    
Concentration risk percentage 0.00% 0.00%
Accounts Receivable [Member]    
Concentration Risk [Line Items]    
Concentration risk percentage 0.00% 0.00%