v3.20.2
Significant Accounting Policies - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Dec. 31, 2019
Accounts receivable $ 162,269   $ 162,269   $ 50,315
Accounts Receivable [Member] | Customer A [Member]          
Percentage Concentration         38.00%
Accounts Receivable [Member] | Customer C [Member]          
Percentage Concentration         21.00%
Accounts Receivable [Member] | Customer E [Member]          
Percentage Concentration     15.00%    
Accounts Receivable [Member] | Customer H [Member]          
Percentage Concentration     11.00%    
Revenue Benchmark [Member] | Customer F [Member]          
Percentage Concentration     11.00%    
Revenue Benchmark [Member] | Customer D [Member]          
Percentage Concentration   12.00%   13.00%  
Maximum [Member] | Accounts Receivable [Member]          
Percentage Concentration     10.00%   10.00%
Maximum [Member] | Revenue Benchmark [Member]          
Percentage Concentration 10.00% 10.00% 10.00% 10.00%