Quarterly report pursuant to Section 13 or 15(d)

Revenue (Major Customers) (Details)

v3.10.0.1
Revenue (Major Customers) (Details)
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Revenues | Customer concentration risk | Fidelity        
Major Customers        
Revenue as a percentage of the company's total 17.00% 17.00% 17.00% 17.00%