Quarterly report pursuant to Section 13 or 15(d)

Customer Concentration (Details)

v3.19.2
Customer Concentration (Details)
3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Dec. 31, 2018
Customer A [Member] | Total Revenues from External Customers [Member]          
Concentration Risk [Line Items]          
Concentration Risk, Percentage 30.00% 27.00% 30.00% 29.00%  
Customer A [Member] | Accounts Receivable from External Customers [Member]          
Concentration Risk [Line Items]          
Concentration Risk, Percentage     19.00%   35.00%
Customer B [Member] | Total Revenues from External Customers [Member]          
Concentration Risk [Line Items]          
Concentration Risk, Percentage 20.00% 22.00% 19.00% 23.00%  
Customer B [Member] | Accounts Receivable from External Customers [Member]          
Concentration Risk [Line Items]          
Concentration Risk, Percentage     26.00%   23.00%
Customer C [Member] | Total Revenues from External Customers [Member]          
Concentration Risk [Line Items]          
Concentration Risk, Percentage 19.00% 22.00% 19.00% 24.00%  
Customer C [Member] | Accounts Receivable from External Customers [Member]          
Concentration Risk [Line Items]          
Concentration Risk, Percentage     26.00%   30.00%
Customer D [Member] | Total Revenues from External Customers [Member]          
Concentration Risk [Line Items]          
Concentration Risk, Percentage 23.00% 20.00% 23.00% 15.00%  
Customer D [Member] | Accounts Receivable from External Customers [Member]          
Concentration Risk [Line Items]          
Concentration Risk, Percentage     25.00%