Revenue - Additional Information (Detail) - Contract
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Disclosure of revenue [line items]    
Number of forward contracts outstanding 0 0
Customer A [member]    
Disclosure of revenue [line items]    
Risk Revenue 33.00% 33.00%
Customer B [member]    
Disclosure of revenue [line items]    
Risk Revenue 32.00% 25.00%