Quarterly report pursuant to Section 13 or 15(d)

Customer Concentration (Details)

v3.19.1
Customer Concentration (Details)
3 Months Ended 12 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Dec. 31, 2018
Customer A [Member] | Total Revenues from External Customers [Member]      
Concentration Risk [Line Items]      
Concentration Risk, Percentage 31.00% 31.00%  
Customer A [Member] | Accounts Receivable from External Customers [Member]      
Concentration Risk [Line Items]      
Concentration Risk, Percentage 35.00%   35.00%
Customer B [Member] | Total Revenues from External Customers [Member]      
Concentration Risk [Line Items]      
Concentration Risk, Percentage 19.00% 25.00%  
Customer B [Member] | Accounts Receivable from External Customers [Member]      
Concentration Risk [Line Items]      
Concentration Risk, Percentage 22.00%   23.00%
Customer C [Member] | Total Revenues from External Customers [Member]      
Concentration Risk [Line Items]      
Concentration Risk, Percentage 19.00% 25.00%  
Customer C [Member] | Accounts Receivable from External Customers [Member]      
Concentration Risk [Line Items]      
Concentration Risk, Percentage 23.00%   30.00%
Customer D [Member] | Total Revenues from External Customers [Member]      
Concentration Risk [Line Items]      
Concentration Risk, Percentage 22.00%    
Customer D [Member] | Accounts Receivable from External Customers [Member]      
Concentration Risk [Line Items]      
Concentration Risk, Percentage 10.00%