Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Concentration of Credit Risk and Significant Customers (Details)

v3.19.3.a.u2
Summary of Significant Accounting Policies - Concentration of Credit Risk and Significant Customers (Details) - Customer Concentration Risk
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Customer A | REVENUES      
Concentration Risk [Line Items]      
Concentration risk, percentage 15.00% 60.00% 29.00%
Customer A | ACCOUNTS RECEIVABLE      
Concentration Risk [Line Items]      
Concentration risk, percentage 73.00% 65.00%  
Customer B | REVENUES      
Concentration Risk [Line Items]      
Concentration risk, percentage 20.00% 8.00% 30.00%
Customer B | ACCOUNTS RECEIVABLE      
Concentration Risk [Line Items]      
Concentration risk, percentage 2.00% 3.00%