Related-Party Transactions (Details) - USD ($)
$ in Millions
9 Months Ended 12 Months Ended
Sep. 30, 2016
Dec. 31, 2015
Rent and facility related fees    
Related Party Transaction [Line Items]    
Payments to related party $ 1.3 $ 1.2
Investor(s) | Professional fees    
Related Party Transaction [Line Items]    
Payments to related party $ 0.1