Quarterly report pursuant to Section 13 or 15(d)

Customer Concentration (Details)

v3.19.3
Customer Concentration (Details)
3 Months Ended 9 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Sep. 30, 2019
Sep. 30, 2018
Revenue | Major customers        
Concentration Risk [Line Items]        
Concentration risk, percentage 56.70% 60.10% 54.60% 61.40%