Quarterly report pursuant to Section 13 or 15(d)

Revenue - Narrative (Details)

v3.10.0.1
Revenue - Narrative (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2018
Jan. 01, 2018
Dec. 31, 2017
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]        
Unbilled receivables, net $ 35,771 $ 35,771 $ 47,069 $ 42,577
Contract with customer, liability 4,400 4,400 $ 9,800  
Contract with customer, liability, revenue recognized 400 8,100    
Revenue, remaining performance obligation $ 345,000 $ 345,000    
Sales Revenue, Net | Product Concentration Risk | Transferred over Time        
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]        
Concentration risk, percentage 57.00% 57.00%    
Sales Revenue, Net | Product Concentration Risk | Transferred at Point in Time        
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]        
Concentration risk, percentage 43.00% 43.00%