Annual report pursuant to Section 13 and 15(d)

Customer Concentration - Additional Information (Detail)

v3.21.1
Customer Concentration - Additional Information (Detail) - Customer Concentration Risk [Member] - Customer
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Revenues [Member]    
Concentration Risk [Line Items]    
Number of customers 3 4
Concentration percentage 66.00% 52.00%
Accounts Receivable [Member]    
Concentration Risk [Line Items]    
Number of customers 4 4
Concentration percentage 92.00% 100.00%