Annual report pursuant to Section 13 and 15(d)

Revenue Recognition - Narrative (Details)

v3.20.4
Revenue Recognition - Narrative (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]      
Unbilled receivables, net $ 22,358 $ 46,279  
Contract with customer, liability 10,100 5,000  
Contract with customer, liability, revenue recognized $ 2,200 $ 2,200  
Concentration risk, percentage 100.00% 100.00% 100.00%
Revenue, remaining performance obligation, amount $ 183,000    
Product Concentration Risk | Transferred over Time | Revenue Benchmark      
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]      
Concentration risk, percentage 51.00% 57.00%  
Product Concentration Risk | Transferred at Point in Time | Revenue Benchmark      
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]      
Concentration risk, percentage 49.00% 43.00%